Agent Carter has several, such as SSR agents Daniel Sousa, Jack Thompson and Ray Krzeminski, along with waitress and friend of Peggy's, Angie Martinelli. The most prominent addition is Dottie Underwood, a villainous assassin who was trained by the Black Widow program. While she shares similarities to comic-based Black Widows such as Natalia Romanova and Yelena Belova, Dottie herself was created specifically for the show.
Melinda May and the others are now officially Canon Immigrants thanks to the S.H.I.E.L.D. series Marvel is putting out.
The show has also moved away from the heavy use of Canon Foreigners in response to the criticism from fans. Characters like Deathlok and Blizzard debuted in the latter half of Season 1, while other comic characters like Mockingbird and Absorbing Man began appearing in Season 2, with more comic characters following in the subsequent episodes.
Subverted with Skye, who—after a season's worth of being this—turned out to be the cinematic universe's version of Daisy Johnson, aka Quake.
Alex Rider: Kyra wasn't in the book version of Point Blanc, where the titular school had only male students.
Legends of Tomorrow has - with the exception of an Alternate Self of The Flash - the distinction of everyone being a Canon Foreigner, including Ava Sharpe, who does not exist in any DC Comics continuity and is entirely original to the Arrowverse.
A fair number of villains in Batman (1966), such as Egghead, Siren, Archer, Black Widow (not that one), Chandel, and Nora Clavicle. A few of them like Bookworm and King Tut became Canon Immigrants.
The Boys (2019): There are many characters added to the show who were not present in the comics, including Translucent (who replaces Jack from Jupiter in The Seven), Ezekiel (who replaces Oh Father), Mesmer, Doppelganger, Frenchie's girlfriend, and Starlight's mother (who was only briefly mentioned in the comics).
Foggy Nelson's girlfriend Marci Stahl is an all-new character created just for the show. Although she has a similar role to Deborah Harris, Foggy's girlfriend and later wife in the comics, she's a much different person from Debbie.
Mitchell Ellison, editor-in-chief of the New York Bulletin, is the equivalent of J. Jonah Jameson.
District Attorney Samantha Reyes in season 2, has no comics counterpart, unlike her subordinate and successor Blake Tower, who is.
Ray Nadeem in season 3 has no comics counterpart.
In Dickensian, where nearly all the characters were created by Charles Dickens, exceptions are Henry Barbary, the father of Miss Barbary from Bleak House and Fanny Biggetywitch who, barring a shock reveal later, appears to be entirely original.
Reed Strucker and his wife and kids in The Gifted. In a unique example, while they don't exist in the comics, they are related to actual comic characters. It is eventually revealed in the first season that Reed is the grandson of Andreas von Strucker, one half of the mutant duo Fenris.
Fish Mooney on Gotham is a created-for-TV character. A number of the show's criminals are new, in fact, so that Batman's entire Rogues Gallery won't get a 15 year head start on him.
Fish's dragon Butch Gilzean started as this, until it is revealed that he is this universe's version of Cyrus Gold aka Solomon Grundy.
This applies to a large number of the supporting and minor characters in Jessica Jones (2015), such as Hope, Jessica's annoying neighbors Robyn and Ruben, and Jeri Hogarth's girlfriend Pam. Many of Jessica's clients also tend to be original characters. Subverted with Will Simpson, as he initially seems like this, only to turn out to be the supervillain Nuke all alongnote He's named Frank Simpson in the comics. The change of first name ostensibly hides the plot twist, and also was done ostensibly to avoid confusion with Frank Castle, who was about to make his debut in season 2 of Daredevil.
In season 2, Pryce Cheng, Inez Green, and Oscar Arocho are entirely new characters invented for the show.
Gaius plays the mentor role now that Merlin himself is a teenager. In some accounts Merlin did have a mentor named Blaise, but for whatever reason they decided not to use him, probably due to a lack of recognition. It would've been easier to just make up a character than use a pre-existing one most of the audience would've assumed was a canon foreigner anyway.
Sir Leon, who became an Ascended Extra following the actor Rupert Young's popularity with the main cast, is the only one of the five main knights who has no basis in Arthurian legend.
Ninja Turtles: The Next Mutation introduced a lot of characters that weren't featured in any previous incarnation of Teenage Mutant Ninja Turtles and, given co-creator Peter Laird's hatred of the show and the show's overall infamous reception, aren't likely to appear in any of Nickelodeon's adaptations any time soon. The most notorious example of all, however, would be the fifth female turtle Venus de Milo.
The Plot Against America: In this adaptation of the original novel, the character of Bess and Evelyn's mother was added to represent the generation who actually came to America and raised families in their new home. Her funeral makes note of this.
How much you consider Power Rangers an adaptation of Super Sentai is variable (depending on the season, some just borrow some fight footage, and some are shot-for-shot remakes) but in addition to non-sentai supporting casts, Power Rangers Lightspeed Rescue has the Titanium Ranger, a Sixth Ranger that doesn't exist in any form in the original series, which it is otherwise quite similar to. The Spirit Rangers may or may not count (the characters existed; that storyline and their getting shiny suits didn't.)
The Shogun Ultrazord from Season 3 of MMPR is an interesting case. The two Zords that combined to create it did originate in the Super Sentai source material, but were from two separate shows. The Shogun Megafalconzord was originally Super Muteki Shogun from Ninja Sentai Kakuranger, while Titanus was Beast Knight God King Brachion from the aforementioned Zyuranger. As no footage of the Shogun Ultrazord existed in any of the Japanese originals, the producers were forced to use the toy itself in the show!
Power Rangers RPM has an attack with the wheels of the suits that didn't appear in Go-onger.
Mio Kuroki was Beryl's "shadow" who could more directly interact with the cast and seemed to have a degree of free will. She was specifically created by Beryl and Jadeite to cause trouble for Usagi at school.
Hina Kusaka and her unnamed father. Said father is Mamoru's benefactor (since his parents are dead) and Hina is his fiancee, which of course causes drama between him and Usagi.
Sugao Saito, Minako's flamboyant manager and IIRC an old friend of Ikuko's.
If alter egos count, there's Dark Sailor Mercury whose name is pretty self-explanatory. She's an evil version of Sailor Mercury who works for the Dark Kingdom after being corrupted by Kunzite (though she's not very obedient).
Kunzite gained a human alias in the form of Shin, who was also an amnesiac. This is notable because Kunzite had no alias in either the manga or anime. Nephrite had the alias(es) Nefukichi/Nefurin when he was a normal human. He briefly would've used an alias in his translator disguise in the manga/Crystal but we never found out what it was and the alias he used in the anime was Masato Sanjouin. In Act Zero we're introduced to four cops played by the Shitennou's actors whose names (exceptHanako's) correspond to the hair colors of those characters.
Motoki gains a pet turtle named Kamekichi. This would be insignificant if not for the fact that in this version Motoki is obsessed with turtles, so Kamekichi is a symbol of that.
The Punisher (2017): Dinah Madani, Sam Stein, and the rest of the Homeland Security cast are all original characters. Elsewhere, Lewis Wilson, a member of Curtis Hoyle's support group, has no comics counterpart, although his bombing rampage bears markings of the comics Nuke.
The 1980s series Robin of Sherwood introduced the idea of including a Saracen in Robin Hood's band of merry men, a figure that was popular enough to be included in Kevin Costner's Prince of Thieves and again in the BBC's 2006 Robin Hood. The latter also introduced original characters Isabella (Guy of Gisborne's sister) and Kate (Locksley village girl) as Affirmative Action Girls after Marian and Djaq (who, ironically, was the Saracen) were written out.
Teenya, the female Martian to whom Sam Conrad is attracted in "People Are Alike All Over", does not appear in the short story "Brothers Beyond the Void" by Paul W. Fairman.
Mrs. Williams, Mrs. Lucas and FBI Agent Hall, the three supporting characters in "Four O'Clock", do not appear in the short story by Price Day.
In "Death Ship", Lt. Ted Mason sees his wife Ruth and daughter Jeannie in the afterlife while Lt. Mike Carter sees Kramer and Mrs. Nolan. None of these characters appear in the short story by Richard Matheson.
In "A Message from Charity", Peter Wood has a younger brother named Bobby. In the short story by William M. Lee, he is an only child.
In "One Life, Furnished in Early Poverty", Gus Rosenthal sleeps with a fan of his whom he met after he delivered a lecture on writing. She does not appear in the short story by Harlan Ellison.
In "Night of the Meek", the Dundee's security guard Henderson is Henry Corwin's Only Friend and helps him to distribute the presents from his magic Santa sack. He does not appear in the original episode.
In "The Star", the commanding officer of the survey ship Magellan is Captain Durant. She does not appear in the short story by Arthur C. Clarke.
"The Misfortune Cookie" features the supporting characters of Harry Folger's editor Max, the eponymous owner of Mr. Lee's Chinese Cuisine and April Hamilton, whom Harry briefly dates. None of them appear in the short story by Charles E. Fritch.
In "A Matter of Minutes", both Michael Wright and his wife Maureen become trapped in a minute that is still under construction. In the short story "Yesterday Was Monday" by Theodore Sturgeon, it is only Harry Wright.
In "Dead Run", Johnny Davis learns of the job transporting condemned souls to Hell from his fellow trucker Pete, who shows him the ropes. Pete does not appear in the short story by Greg Bear as Johnny has already been doing the job for two years.
In "The Last Defender of Camelot", Tom is one of three punks hired by Morgan le Fay to bring Lancelot to her. Lancelot later takes Tom as his squire and brings him to the cave in Cornwall to meet the newly awakened Merlin. Tom does not appear in the short story by Roger Zelazny. He was added at the insistence of CBS executives who thought that Twilight Zone stories should always feature ordinary people in extraordinary situations.
The Vampire Diaries has a few, mostly family members of canon characters. Jeremy qualifies as well—he's too far different and fills such a completely different role in the story from Elena's younger sister in the books that he can't be considered the TV version of her.
A lot of characters in The Walking Dead never appeared in the comics including Daryl Dixon, Merle Dixon, Beth Greene, Leon Basset, Gary Taylor, Patty Taylor, Jacqui, the Morales family, Dr. Jenner, Guillermo, Jimmy, Dave, Tony, Randall Culver, Nate, Sean, Oscar, Big Tiny, Rowan, Haley, Tim, Shumpert, Crowley, Gargulio, Karen, Noah, the Grady Memorial Hospital police officers, Aiden Monroe, and Enid.
Daryl is the most popular with the comic's creators, going so far as to say they would never make him a Canon Immigrant as the character is so well established in his own continuity that their version couldn't do justice to him.