During an interview with the New York Times, Walter Hamada, head of DC films at WB mentioned we would be seeing two different versions of Gotham on the big screen.
Warner Bros. will have two different film sagas involving Batman, played by two different actors, running at the same time.
-Walter Hamada
Many assumed these two different takes would involve Robert Pattinson whom is currently filming The Batman with Matt Reeves, and Ben Affleck who will reprise his role as Batman in Zack Snyder’s Justice League and The Flash. But people also seem to have forgotten that Michael Keaton is also set to reprise his role in The Flash and as reported by trades he will have a significant role to play not only in that movie but in the larger DC film universe.
So obviously there was some confusion, would Keaton or Affleck be the main Batman moving forward. Well now thanks to the author of the New York Times piece, Brook Barnes we have confirmation that Keaton will indeed be the second and main Batman for DC films and he will not only show up in The Flash but will feature in the universe a whole and make appearances in other projects including Batgirl.
So it looks like moving forward Keaton and Pattinson will be your live action DC Batmen and will carry the Dark Knight mantle in two separate Earth’s in the DC universe. What does this mean for Ben Affleck, well it likely means he is done as Batman after The Flash and we could conceivably see him say goodbye in some form in that film as a last hoorah for himself and fans.
Source: Brooks Barnes