The multiverse plot of The Flash opens the door for Robert Pattinson's Batman to appear, but will he? The DC Extended Universe is in a very different place as Ezra Miller's long-awaited solo movie for the Scarlet Speedster approaches compared to when The Flash started development. Warner Bros. and DC Films have slowed down plans to build a tightly connected superhero cinematic universe to rival Marvel. The focus is instead on creating unique, character-focused stories first, which includes a rough adaptation of Flashpoint for The Flash and a new standalone Batman franchise starring Robert Pattinson.
After a few years of Ben Affleck playing the Dark Knight for Zack Snyder, the DCEU is taking Batman in a new direction moving forward. Director Matt Reeves has created The Batman as a reboot that brings the noir and detective elements of Bruce Wayne to the forefront. In order to do this properly, though, Robert Pattinson's Batman will exist outside of the main DCEU continuity. That universe consists of everything from Man of Steel to Wonder Woman to Joss Whedon's Justice League to The Suicide Squad. Still, questions persist about whether or not Pattinson's Batman could join the regular DC universe or be directly connected to it through the multiverse. This is where The Flash could come into play.
Even though The Flash is a perfect place to feature a crossover, the odds of Robert Pattinson's radically different Batman appearing don't appear to be high. It is clear from The Batman's marketing that Matt Reeves is taking a very specific approach to the franchise. Furthermore, WB and DC seem to be thrilled with the Batman-centric universe he's building. There are two HBO Max spinoff shows already in development, and more could come after The Batman, which is also sure to get a sequel movie. The separate continuity is allowing The Batman to not have to worry about any past or upcoming DCEU films, and that creative freedom has delivered great early results. Changing course to include Pattinson's Batman in The Flash and tying him to the main DCEU continuity is unnecessary at this stage and might even hinder the future.
It's also worth noting that The Flash is already filled with Batman even without Robert Pattinson. The movie is confirmed to bring Ben Affleck back as the DCEU's Batman. It is widely believed this will be his last appearance, though, so a new Dark Knight could be needed. However, The Flash could hold the answer, but again without involving Pattinson. Michael Keaton is confirmed to return as the Caped Crusader for the first time since 1992's Batman Returns. He could stay in the main DCEU timeline too. Beyond Batman's future in the DCEU, Affleck and Keaton will give The Flash more than enough of a Batman presence. Including Pattinson's version would be too much and make The Flash feel even more crowded.
As unlikely as it seems that Robert Pattinson's Batman will be in The Flash, it is always possible that WB and DC could force a cameo in at some point in the film or even during the post-credits. Such a move would be enough to create a connection between Pattinson and the main DCEU, giving the studios the ability to eventually bridge the gap if they want. Fans are already quite enthralled by Pattinson's Batman, so the clamor for him to be in the DCEU is likely to rise moving forward. But, since both The Flash and The Batman are starting points for new franchises, a tease for that potential crossover would be better saved for the future.
