In "Överenskommelser", we have Beatrice as the Sanguine, Seth as the Choleric, Sofia as the Phlegmatic and Johan as the Eclectic.
In ''De skandalösa", Magdalena as the Melancholic, Gabriel as the Sanguine, Venus as the Phlegmatic and Ossian as the Eclectic.
In The Anderssons by Solveig Olsson-Hultgren, you can see the four original Andersson sisters as this: Elin is the Choleric, Mandi is the Phlegmatic, Ida Sofia is the Melancholic and Greta is the Sanguine.
A Christmas Carol: Ebenezer Scrooge (choleric), The Ghost of Jacob Marley (melancholic), The Ghost of Christmas Past (eclectic), The Ghost of Christmas Present & Tiny Tim (sanguine), Bob Cratchit & The Ghost of Christmas yet to come (phlegmatic).
A Clockwork Orange: Alex (melancholic), Dim (sanguine), Georgie (choleric), and Pete (phlegmatic).
American Gods: Shadow (phlegmatic), Mr. Wednesday (choleric), Czernobog (melancholic), and Mr. Nancy (sanguine).
In The Armadillo with No Heart, one of these is formed when the armadillo protagonist, Kuro, joins a group of three hedgehog bandits. Kuro is fearful, shy, and lacking in self-esteem (melancholic); Morty is a kind-hearted Gentle Giant who adopts a protective attitude towards Kuro (phlegmatic); Gus is playful and childlike (sanguine), and the group leader, Clyde, is rough and abrasive (choleric).
The original four members of The Baby-Sitters Club: Kristy (choleric), Mary Anne (melancholic), Claudia (sanguine), and Stacey (phlegmatic).
The Bad Guys series has the five main members of "The Good Guys Club": Mr. Wolf, as the open to change leader that believes the others can become good (sanguine), Mr. Snake as the sarcastic doubter that still can't shake his evil side (choleric), Mr. Piranha as the realistic and dry member that's hiding obvious stress (melancholic), Mr. Shark as the threatening-looking, yet warm hearted and able to blend in with others (phlegmatic), and Legs, the optimistic tinkerer that doesn't let others' opinions effect him (eclectic).
The Bailey School Kids: Eddie (choleric), Liza (melancholic), Howie (phlegmatic), and Melody (sanguine).
The D Squad in The Homework Machine:Kelsey (sanguine), Snik (choleric), Judy (melancholic), and Brenton (phlegmatic).
The Horus Heresy novels, set in an earlier era of Warhammer 40,000, toy with this openly with Warmaster Horus' inner advisory circle during the first few novels, consisting of Ezekyle Abaddon (choleric), "Little Horus" Aximand (melancholic), Tarik Torgaddon (sanguine), and Garviel Loken (phlegmatic).
In In the Time of the Butterflies by Julia Alvarez (a dramatization of the lives of the Mirabal sisters from the Dominican Republic), Maria Teresa "Mate" Mirabal (sanguine), Minerva Mirabal (choleric), Dede (melancholic), and Patria (phlegmatic).
The four boys in the camp plot of Jelly Belly: Protagonist Ned (melancholic), Richard (choleric), Hog (phlegmatic), and Max (sanguine).
The Monkey Wrench Gang: Doc Sarvis (sanguine), Hayduke (choleric), Smith (melancholic), and Abbzug (phlegmatic).
On the Road: Sal Paradise (sanguine), Dean Moriarty (choleric), Carlo Marx (melancholic), and Marylou (phlegmatic).
Phantom's Reckoning 2: Yuki (melancholic), Kaori (phlegmatic), Shoji (sanguine with some choleric), and Tatsuya and Makoto (choleric).
In The Poisonwood Bible, the Price ladies minus Ruth May fit this: Rachel (sanguine), Leah (choleric), Adah (melancholic), and Orleanna (phlegmatic).
In Red Mars, psychologist Michel Duval slots the classical temperaments into his own psychological theory: Sanguine = Extroverted + Stabile; Choleric = Extroverted + Labile; Phlegmatic = Introverted + Stabile; Melancholic = Introverted + Labile.
The Roman Mysteries: This is actually explictly stated in the books, which is justified because it takes place during a time period when doctors still believed in the four humors.
Also, the later books have the four eldest Marshall brothers: Joe Jr. (choleric), Jack (phlegmatic), Bobby (sanguine), and Ted (melancholic).
Sammy Keyes and her friends: Sammy (choleric), Dot (melancholic), Marissa (phlegmatic), and Holly (sanguine).
Carmen, Tibby, Bridget, and Lena spend their first summer apart in The Sisterhood of the Traveling Pants. Carmen snaps and gets mad (choleric) so she comes home expecting Tibby to understand because Tibby walks around screaming, "Screw the world" because that's easier than feeling something (melancholic). Carmen and Tibby visit Bridget who talks about her mother and she tells her friends that she just wants to feel good and happy and alive (sanguine). The last one to join them is Lena who feels so sad that people like Kostas and Bridget who have lost everything can still be open to love while she, who has lost nothing, is not (phlegmatic).
The four protagonists of Sleepers by Lorenzo Carcaterra: Michael (choleric), Tommy (melancholic), John (sanguine), and Shakes (phlegmatic). Interestingly, the four abusive guards at the reform school fit this paradigm rather neatly as well: Nokes (choleric), Styler (melancholic), Addison (sanguine), and Ferguson (phlegmatic).