I don’t think that version of the Justice League is one WB or much of the audience is particularly keen to see more of, though. If we do eventually get some sort of Justice League DLC I’d imagine it’d be comic based rather than the film.
Also not helping Batfleck is his lack of solo material, which I’m sure made him even easier to pass over here. Maybe if they do some general DC /JL sequel in the future they’ll mine from those films, but as of now it’s pretty understandable why he’s not a priority.