Most of the iconic characters are voiced by their original film actors and actresses who returned after 30 years or more from their original appearances.
Out of all the available characters, Figment, Mowgli, Celia, Randall, Lilo, Jumba, Oswald, Ursula and Wreck-It Ralph are the only ones to not have their voice actors reprise their roles. Christopher Swindle and Eliza Schneider both reprised their respective roles as James P. "Sulley" Sullivan and Elizabeth Swann from the "Kingdom Hearts" video games series while Danielle Bisutti, Jake Green and Laura Silverman reprise their respective roles as Elsa, Olaf and Vanellope Von Schweetz from "Disney Dreamlight Valley"