The Flashpoint movie will mark the third adaptation of the storyline, the previous two being the animated movie Justice League: The Flashpoint Paradox and the first episode of The Flash Season 3, although the latter explored the consequences of Barry’s temporal meddling for the rest of the season.
If Wonder Woman does indeed appear in the Flashpoint movie, it’s likely that Jason Momoa will also appear as Aquaman so the Amazon-Atlantean War can be properly realized.
Let’s also not forget Ray Fisher and Henry Cavill potentially reprising Cyborg and Superman, respectively, as the former is the U.S.’s top superhero and the latter has been imprisoned by the U.S. government his whole life.
As for Batman, he died in this timeline, and Thomas Wayne (played by Jeffrey Dean Morgan in the DCEU) took on the mantle instead, but there could still be room to fit in Barry Allen visiting the Caped Crusader after the timeline has been restored to deliver a special gift.