Killer Croc's last name is changed from "Jones" to "Morgan", though his real name was given as Waylon Jones in issue 23 of the tie-in comic Batman & Robin Adventures.
Werewolf Anthony Lupus is given the slightly less blatant Werewolf Theme Naming Anthony Romulus.
The series changed the name of Weather Wizard's brother from Clyde to Ben.
Kara Zor-El is renamed "Kara In-Ze". This was due to Executive Meddling. At the time DC had a mandate that Superman was the last Kryptonian left. This meant that Supergirl was Exiled from Continuity (and is why Matrix and Linda Danvers were created). To get around this, the makers of Superman The Animated Series simply gave Kara a new last name (which actually was her mother's maiden name) and said she wasn't from Krypton, but a sister planet that also ended up destroyed. Kara In-Ze was otherwise used interchangeably with Kara Zor-El, besides the fact she was Superman's adopted cousin rather than his biological one.
The episode "Two's a Crowd" was based loosely on the "Doc Parasite" storyline in the comics, except that the scientist Parasite absorbed was named Earl Garver rather than Torval Freeman (and had a Race Lift from black to white).
In the pilot, Lara's father is named Sul-Van rather than Lor-Van, which in turn makes Lara's maiden name Lara Sul-Van.
Batman Beyond featured the animated debut of lesser-known Batman villain Spellbinder, but changed his first name from "Delbert" to "Ira".
Hotstreak went from Martin "Biz Money B" Scaponi to Francis "F-Stop" Stone.
D-Struct's real name was changed from Damon Briggs to Derek "D.B." Barnett.
Rubberband Man went from Karmon Stringer to Adam Evans, though he still uses Stringer as a nickname and alias.
The Night Breed are loosely based on the Blood Syndicate, with Tech-9's equivalent being named just Tech.
Nina Crocker/Timezone is based loosely on Blood Syndicate member Sara Quinones/Flashback, though she is curiously named Flashback in the end credits of her episode.
