The DC Universe’s Elseworlds banner is intended to be used as a way to release movies and shows without requiring them to be tied to the main timeline and universe of the DCU itself. This opens up a host of possibilities for the franchise and ensuring successful series like The Batman can continue in their own cinematic corner.
While it’s unlikely the original plans for Justice League 2 would be greenlit for Elseworlds exactly the same as they were imagined, releases like Justice League: The Flashpoint Paradox movie show that DC isn’t afraid to verge close to the kind of plotlines the movie would entail. As such, it still isn’t impossible that the release could emerge in some transformed shape further down the line. Similarly, while Snyder has discussed moving away from the superhero genre, he’s also discussed being willing to work with DC again in the future, meaning that a slim chance does still remain.
ZACK SNYDER’S JUSTICE LEAGUE: PART 2 STORY Witnessing the defeat of Steppenwolf, the true villain Darkseid prepares his massive Apokoliptian army for a full-scale invasion of Earth. Batman has visions (possibly caused by Scarecrow’s fear toxin) of a dystopian future ruled by Darkseid and Superman under his control. The League is reunited with new heroes such as Green Lantern (Hal Jordan), who foretells the impending attack. On Earth, a temporary resistance made up of heroes like Shazam, Mera and Deathstroke is quickly overwhelmed by Darkseid’s forces. The Justice League returns to Earth to face Darkseid’s armada in an epic showdown.