Snyder has been open about his now-scrapped plans for Justice League 2 and 3, explaining that, after Lois Lane's death, Superman was set to succumb to Darkseid's Anti-Life Equation – then after some time traveling from the remaining Leaguers and their allies, Batman would sacrifice himself to save Lois, and Superman would help in the fight against Darkseid in the trilogy's final installment.
At the fan-organized Justice Con event, though, Oliva talked about what might have happened next. Responding to comments about the end point of Snyder's plans for the DCEU, Oliva said: "Yeah, I mean, I think that was the plan, was that they would do like the four or five parters and then we would do a Flashpoint kind of reboot, where you can bring in a new cast afterwards."
In the Flashpoint comic book story, Barry Allen accidentally ruins the main timeline after traveling back in time to stop his mother's death. While Barry eventually manages to fix his mistake, it resets the DC comic book universe. It, therefore, makes sense a direct adaptation of the story would be an opportunity to reboot and start fresh.
The Flash movie, set for a 2022 release, is thought to take inspiration from this story, and at one point in development, it was even called Flashpoint. The film will see the return of Michael Keaton's Batman, as well as Ben Affleck's version of the vigilante, so expect the multiverse to come into play, too.
Though DC fans have been petitioning Warner Bros. to continue with Snyder's vision for the DCEU, trending hashtags including #RestoreTheSnyderVerse, #DeathstrokeHBOMax, and #MakeTheBatfleckMovie, it seems an unlikely possibility. Snyder himself evaded confirming or denying anything at Justice Con, but Warner Bros. CEO Ann Sarnoff poured water over hopes for any continuations, and a recent trailer billed Zack Snyder's Justice League as "the completion of Zack Snyder's trilogy."