If you can't actually pin characters into the archetypes then you probably don't actually fit the trope, at best having a different Power Trio arrangement. Yes, that's right, your three characters don't have to fit every trio trope. Bear in mind in fact that The Hecate Sisters is the slightly less precise trope with a more basic resonance.

Disputed examples moved here:

• In Mahou Sensei Negima, Negi's friend/rival Kotaro ends up living with Natsumi (child), Chizuru (wife) and Ayaka (Seductress; Crone according to Kotaro).
  • Poor Natsumi, just because she's the shortest, she has to be the child? Really, looking at their relationships with Kotaro, Ayaka is a non-romantic (at least, so far) type-B tsundere, and acts far more childish than Natsuki. Chizuru actually tends to be the most flirtatious, and the most dangerous to Kotaro. ("Don't fall in love with her!") Natsumi, meanwhile, generally has the most mature relationship with Kotaro, and it isn't missed on most readers that their relationship most resembles that of a couple.
    • Part of that is Character Development. Natsumi's the Child not just because of her (lack of) figure, but because that's how she sees herself (example: she uses the 'neechan' honorific for Chizuru, despite the fact that Natsumi is actually a few months older), especially compared to the other two. Chizuru is the wife because she's basically the head of this family unit and is basically learning childcare in her after-school time; Marshmallow Hell notwithstanding, she's the one who started nudging Natsumi towards Kotaro in the first place. Leave Ayaka alone in a room with Negi for about fifteen minutes and you'll see why she's the third.

• Firefly has Kaylee as the child, Zoe as the wife and Inara as the literal seductress— it's her job as a companion (a high-class hooker). River also has some childlike elements (in a Creepy Child sort of way), but is largely outside the archetype. Inara can be thought of in the mother role, given her relationship with most of the non-Mal characters and the calming voice of assurance and goodwill. Zoe also fits, but she seems more like a grown up Action Girl.
  • Could also be re-organized into Kaylee and River each forming one-half of the "child" personality. Though each has innocent and childlike qualities, Kaylee is also much more sexual than the traditional "child" role, and River has that whole psychic/psychosis thing going on. This is displayed in the two forming an innocent, genuine friendship with one another.

• The Golden Girls. Dorothy is the cold and authoritative matron, Rose is the ditzy and innocent child, and Blanche is the Casanova with the most smutty past (and present) love life.
  • Another interpretation would make Sophia the mother, as despite her snarky ways she cares for all the girls. Rose and Blanche have on more than one occasion admitted that they view Sophia as a mother to them.

Deleted these as not fitting: look for weasel words like "kind of" or "sometimes", or for descriptions of the seductress that dance around, and gloss over whether she fits the "sexual" part. Also look for weaseling over which one fits which role. In a Three Faces Of Eve, who is which one is clearly distinguishable. There's no question of which one is Child and which is Seductress. It's not a case of "these two could be either one" or "this character is both of these". It's also a group of three, not four or five or six or more.

• Mai-HiME's main Power Trio falls into this, too: Mikoto Minagi as the Child, Mai Tokiha as the Wife, and Natsuki Kuga as the Seductress...kind of. (Just watch the last few minutes to episode 9...you'll know what we're talking about.) One would expect Mai's and Natsuki's positions to be switched, but hey...
• The Prince Of Tennis girls: Tomoka Osakada is The Maiden (childlike, cheerful, Tsundere), Sakuno Ryuzaki is The Mother (quiet, gentle, protective), An Tachibana is The Seductress (outspoken, assertive, manipulative but good hearted).
• The female Servants of the 5th Holy Grail War. Saber is probably the Child (least developed body, turning out like a Fish Out Of Water when taken to a date by Shiro, and rather awkward in anything outside battle), Caster is the Mother (doesn't have children, but her interactions and utmost loyalty to Kuzuki is almost like a twisted Yamato Nadeshiko) and Rider is the Seductress (Boobs Of Steel and all. And when she is an enemy, she sounded alluring, not to mention that her identity is the Always Chaotic Evil monster Medusa, while Seductresses in general often get bad raps.)
  • Plus, Caster or Medea was a mother. Not a good one, but still. Also, Rider can make people dream of sex.
• Shugo Chara has Amu's three Shugo Charas: Ran is the child, Suu the mother (but with some child-like attributes). Miki, however, is less a seductress than the Only Sane Man (or, better, woman).
• In Candy Candy: female lead Candy is the Seductress (outspoken, strongwilled, defiant of society), her school friend Patty is the Mother (sweet, booksmart, mature), and Candy's best friend and sworn sister Annie is the Child/Maiden (insecure, reserved, sometimes childlike).
• The first half of the original Sailor Moon series has Usagi/Moon as The Child/Maiden, Ami/Mercury as The Wife, and Rei/Mars as The Seductress. Makoto/Jupiter and Minako/Venus make it a Five Man Band soon, though.
  • Also, the Outer Senshi can be seen as this. Haruka is The Maiden (brash, free-spirited, tomboyish), Michiru is the Seductress (gentle, feminine, elegant), Setsuna is The Wife (mature, the oldest of the group, Chibi-Usa's Cool Big Sis).
• AIR has this to a certain extent, with the three main girls. Sweet and mature Minagi is definitely the mother, and while Kano and Misuzu both have aspects of seductress (Misuzu is blatantly obsessed with Yukito, but Kano is playful with him too) Misuzu has many more child traits than Kano does.
• If you add in Cheryl Blossom, she becomes The Seductress of the Archie Comics with Betty (mother) and Veronica (child). Otherwise, Veronica can manage to fill in child and seductress by herself.
• The three female leads of the Harry Potter series loosely fit this — Hermione (mother), Ginny (seductress) and Luna (child). Ginny doesn't quite fit the part of the seductress as well as some fans think, but she's definitely the brash/edgy one, although she occasionally leans towards the child role. Hermione and Luna, on the other hand, fit their respective roles very well.
• The main characters of Avalon Web Of Magic are three teenage girls: nurturing and sensible Emily (mother), selfish and impulsive Kara (child), and the dark outcast Adriane (not a seductress, but definitely Darker And Edgier).
• In Mexican literature, three common representations of women are Malinche (Cortez's mistress) representing the whore or traitor; Mary, the mother of Jesus, representing the Virgin and Sor Juana (an educated nun and early feminist) representing a third option, somewhat intermediate option.
• Buffy The Vampire Slayer, in the high school years, has Buffy (the mother/protector), Willow (the child/innocent), and Cordelia (the seductress).
  • In later seasons, Willow gains elements of the seductress. Tara and Dawn can also represent the mother and child figures respectively.
    • Faith, Glory, and Darla all qualify as seductresses. Drusilla can also fill the "child" slot.

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Where is the "mother" aspect?

• In Revolutionary Girl Utena, Himemiya Anthy. As the Eve figure of Ohtori, she deconstructs all three sides of the child, wife, and seductress triad. In the first arc, Anthy seems like a placid, eerily submissive Damsel In Distress who has no clear will of her own. Her innocence is assumed by the audience, when presented with her domestic Yamato Nadeshiko exterior, and moments of blank, somewhat vapid cheer. However, it later becomes apparent that this image is a counterfeit one, and is slowly replaced by flashes of a far more disturbing persona. This is emphasized through her relationship with Akio. In these scenes, she is depicted as a coldly beautiful goddess — or distant, terrifying witch — more than capable of manipulating those around her. Her role in the dueling game is further emblematic of this whore/crone/maiden dichotomy she represents. As the Rose Bride, she is perpetually on the cusp of maidenhood; she isn't precisely a "girl," or a true adult either.
• The leads in Friends fall under this trope very loosely. Monica is the mother, albeit a neurotic, obsessive-compulsive one; Phoebe is usually the child, but can be the seductress if need be; and Rachel is somewhere between being the child and the seductress, going back and forth when the plot demands it.
  • Note how it swings back and forth between Rachel and Phoebe. When one is being childlike and naive and needs to ask the other for advice, the other one becomes the seductress
    • Phoebe's personality is quirky and hippie-ish, Rachel is (initially) very naive. Rachel probably qualifies better as the seductress because she has had more love interests and is often trying to get dates with guys she likes. Phoebe is much less romantic and her relationships tend to last longer. Phoebe has childlike notions about some things (she thought her mom was a cat) and Rachel simply didn't understand certain social conventions.

(gruff and sharp-tongued isn't "Wife" in TFoE; it's Crone and it's part of Hecate Sisters)

• Whose Line Is It Anyway usually fell victim to The Smurfette Principle, until the creators' attempts to add female talents to expand the ranks wound up invoking this trope in the long run.
  • In the UK run, the three most notable female players were Josie Lawrence ("the child", despite being up the most often), Sandi Toksvig ("the mother", a gruff and sharptongued Ladette), and Caroline Quentin ("the seductress", responsible for some of the filthiest jokes on the show).
  • In the US run, there's Kathy Greenwood ("the child", also appeared the most), Denny Seigel ("the wife", able to be as gruff and loud as the men), and Karen Maruyama ("the seductress", known for her Me Love You Long Time and Mrs Robinson acts).

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Crone and Maiden aren't Three Face Of Eve — they're Hecate Sisters, and that's a different trope. Maiden is different from Child; and Crone and Seductress are also different.

• The Twelve Kingdoms: Shoukei is a mix of Crone and Maiden (was utterly spoiled and sheltered as a young girl, then is subjected to a huge Break The Haughty), Youko Nakajima/Sekishi/Yoshi used to be Maiden/Child but is now Wife/Mother with small touches of Crone (goes from an Ordinary Highschool Student to the Queen of Kei), and Suzu is a full-on Maiden/Child (worked as a maid, then started travelling).
• Fruits Basket:
  • Also Tohru Honda and her friends: Tohru herself is The Child (with touches of Mother), Hana is The Mother, Uo is the Crone
• The three more developed female nations in Axis Powers Hetalia: Hungary is the Mother, Belgium is the Crone, Liechtenstein is the maiden.
• Marmalade Boy gives us the three main girls: Miki Koishikawa (Maiden), Meiko Akizuki (Mother) and Arimi Suzuki (Crone). Other girls can fit in too, specially in the TV series: Anju and Doris are clearly Mothers, while Suzu and Yayoi are Maidens and Jinny is Crone.
• The Card Captor Sakura TV series gives us Sakura Kinomoto (Maiden), Tomoyo Daidouji (Mother) and Li Meiling (Crone).
  • And Sakura's school friends, both in manga and anime: Naoko Yanagisawa (Maiden), Rika Sasaki (Mother) and Chiharu Mihara (Crone).
• Because of consistent cast changes, Puella Magi Madoka Magica has quite a few sets of these:
  • Originally we had Madoka Kaname as the Maiden (naive, child-like, cute), Sayaka Miki as the Crone (more in the sense of being a Plucky Girl than real seduction, and she also had some Mother touches due to being very devoted to Madoka and Kamijou) and Mami Tomoe (a Lady Of War, the most experimented in Magical Girldom, very serene) as the Mother. And then Mami got killed off.
  • Later, Madoka remains as the Maiden, with the brash and Hot Blooded Kyouko Sakura as the Crone, and Homura Akemi becoming a rather aloof (in looks) Mother. Sayaka was a mix of Maiden and Crone, but after turning into a Witch, she completely became Crone. And then, Kyouko showed Mother traits and pulled a Taking You With Me for Sayaka.
  • In school: Madoka still was Maiden, with Sayaka as the "Crone" and the local Yamato Nadeshiko Hitomi Shizuki as the Mother. Though Hitomi showed some Crone touches when she decided to speak to her and Sayaka's common crush Kamijou, and Sayaka... well...
  • And episode 10 gave us another one: In the original timeline, Homura actually was the Maiden, since she used to be a Cute Clumsy Meganekko. A more self-assured Madoka who has become a Magical Girl is now the Mother, and a Mami quite similar to the one we met before is the Crone.
    • In the Grand Finale, though, Madoka fully graduates from Maiden to Mother. And then she Ascends To A Higher Plane Of Existence.
• Shamanic Princess: Tiara is the Crone, Sara is the Maiden, Lena is the Mother. Or are they?
• Umineko No Naku Koro Ni has the three Ushiromiya aunts: Natsuhi (responsible, proper, serious Mother), Eva (young-looking, Rich Bitch Crone) and Rosa (troubled, emotional, sometimes violent Child). Yep, they're technically all moms, but personality-wise they fit the trope. And are more complex than they seem.
• Sandman:
  • Let's not forget the Three, who've manifested as the Fates and the Kindly Ones, always taking the form of the maiden-mother-crone triad. The Three itself/herself/themselves state that Eve "is in herself an aspect of us [the Three]".
• The three Fates also pop up again in American Gods.

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This is an Always Female trope. If one or more of them is male it isn't this trope.

• Tenshi Ni Narumon might be a little unusual example but by the end of the series we a have our Power Trio consisting of Noelle, Silky and Mikael and although Mikael is a male, it still somewhat fits. Noelle represents the Child (totally pure and innocent with a brain of 3-year old), Silky is the Crone (she's the most powerful of the trio and acts on her own with shades of the Maiden) and Mikael is the Mother (mostly because of his slightly twisted caring attitude towards both Noelle and Silky, although he has some shades of the Seductress)
  • Mikael, although male, himself has all the three sides - yes, you heard me right, the three faces of Eve, and not of Adam: in the first season and most of the time when he's around Noelle, he's the Mother - acting with a caring and gentle kindness towards her. In the second season - mostly when around Raphael - he's the Child: stubborn, insecure and needy. And in the last episodes, he's the Seductress/Crone - evil and insane, using his powers to try and make Noelle and Silky (and himself) angels
• Brad, Randy, and Mark. Think about it.
• Two And A Half Men is an interesting male version, with Charlie, a big ladies' man and often a Deadpan Snarker; his brother Alan, a geeky, awkward guy who just got out out his divorce: and Jake, Alan's son from his former marriage. Consider, except for gender, it is more accurate then most of the examples on this page.
  • Interesting in that this fits The Three Faces Of Eve better even than it fits the regular Power Trio.

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Re: Girl Genius.

No doubt Zeetha would be the Seductress, but who would be the Child? The Wife?

Could Agatha be the Child or the Wife?