The Reboot and the New Batman Film
The DCU's Batman is already unlike the DCEU's. Following the release of Aquaman and the Lost Kingdom, the DCEU will be rebooted into the DCU, led by James Gunn and Peter Safran. At the beginning of 2023, James Gunn made a series of announcements regarding the DCU, including a new Batman film titled Batman: The Brave and the Bold. The film does not star Ben Affleck nor Robert Pattinson and will be a fresh iteration of the character presumably based on Grant Morrison's comic book run, Batman and Son.
Custom image of Christian Bale, Robert Pattinson, and Ben Affleck as Batman.
No cast or director has been attached to The Brave and the Bold, but the comic book it's based on gives audiences some information on what the film will include. The movie will likely center around an older version of Bruce Wayne, alongside his kid, Damian, and possibly the multiple other Robins who have flown under Batman's wing. The confirmation of Robin fixes an off-screen death from the DCEU that caused quite a stir for DC audiences.
Ben Affleck's Batman looks at a display of a Robin suit
DCU's Batman Undoes the DCEU's Controversial Character Death Reveal
Batman v Superman: Dawn of Justice featured a version of Batman that some disagreed with. While most appreciate Affleck's performance as an older, disillusioned Bruce Wayne, others were upset that his character killed people and fought with brutal violence. One reason for his more bloodthirsty attitude could be that Robin was killed. It's shown later that Bruce keeps Robin's old suit in a display case, and the suit has graffiti on it that says 'Joke's on you, Batman', suggesting the Joker murdered Robin sometime in the past.
Ben Affleck's Batman fighting in Batman v Superman Dawn of Justice warehouse scene
Zack Snyder did confirm that this Robin was Dick Grayson, and he was killed off-screen. This decision caused controversy among viewers as it eliminated many great storylines from Affleck's Batman and used Robin as an emotional excuse for Batman to turn violent. Affleck's Bruce Wayne didn't have an origin story, but this reveal teased audiences about important aspects of this character that they never got to see. Gunn's announcement about Robin in the DCU redeems this decision from the DCEU and gives audiences the chance to see Batman and Robin's relationship unfold.
Ezra Miller as the Flash, Ben Affleck as Batman, and Gal Gadot as Wonder Woman in Justice League
The Exact Opposite: Setting Up the DCU's Batman
The Batman and Son comics storyline features several of Batman's kids, including Damian Wayne and Tim Drake. In Gunn's announcement, he said that this story would include Damian, who he called his 'favorite Robin' and 'the beginning of sort of the Bat Family in the DCU.' The DCU's Batman will not be an isolated introvert who doesn't have any relationships outside of Alfred.
Ben Affleck as Bruce Wayne's Batman in Knightmare scenario
This will be a drastically different version who tries to connect with his kids, and it could also be a more sociable Bruce Wayne, who portrays himself as a charming aristocrat. Damian also has a connection to Talia al Ghul, so the pantheon of Batman characters in Batman: The Brave and the Bold could be introduced immediately. It also looks to be a more personal story rather than one that connects to Superman, Wonder Woman, and the larger DCU - at least in part.
Ezra Miller as the Flash and Ben Affleck as Batman in Justice League (2017)