All of the individual Justice League members are receiving standalone movies, from The Flash and Aquaman to Wonder Woman.
Superman started this phase of the DCEU with Man of Steel, but his sequel was quickly co-opted to include Ben Affleck’s new Batman for Dawn of Justice.
Could one of those hold Man of Steel 2?
Right now, there are untitled DC superhero movies down for Oct. 5, 2018 and Nov. 1, 2019.