This is all made possible by the fact that this Joker origin movie will be set in a different universe aside from the DCEU.
There has been talk for quite some time about Warner Bros. developing a separate DC movie universe aside from the DCEU, and it seems this untitled Joker origin movie will fall within that untitled universe.
Deadline reported that this Joker movie starring Joaquin Phoenix is still in the works.
This new report claimed that the untitled Joker origin movie, “is still in development and will fall under a different DC origins cinematic banner, to separate it from the titles set during the current day.”