According to Michaela Jill Murphy, who played Toph in Avatar: The Last Airbender under the stage name Jessie Flower, it's doubtful that the original cast will reprise their roles in the upcoming animated films. Murphy shared her thoughts at MomoCon (as reported by Comicbook.com), stating that while she would be willing to return as Toph, it's unlikely to happen.
As an actor, receiving a call back for a project is always exciting. However, in the industry, recasting is a common occurrence and it's unlikely that people will demand for the original cast to return. In the case of [the show], despite fans requesting for a fourth season, the creators had a specific vision and chose not to continue the series. While I am personally disappointed that I won't be returning to the show, I'll still be supporting from the sidelines like any other fan.
What To Expect From The Last Airbender Animated Film
Given that the Avatar: The Last Airbender movie will showcase an older version of Aang and his companions, it's understandable that the original cast won't be reprising their roles. Not much is known about the upcoming film, but it has been confirmed that the storyline will take place between the events of Avatar: The Last Airbender and its sequel, The Legend of Korra. This opens up the possibility for the movie to address any unanswered questions from the TV series or introduce a fresh challenge for Aang and his friends to tackle.
The Avatar: The Last Airbender franchise is set to grow bigger with the production of a live-action series for Netflix, reportedly with a high budget. Paramount has also confirmed that two additional animated films are in development, in addition to the previously announced 2025 release of an animated film. While it's disappointing that the original cast won't be returning, the franchise's continued expansion suggests that there is still much to look forward to in the future.