If and when the Justice League comes back together is unknown, and what they’ll be doing when that happens is even less clear.
The future of DC’s films, as far as what we know for sure is on the way, is a series of solo projects for Aquaman, Wonder Woman, and Shazam.
Of course, now, whether or not we’ll ever see Darkseid is unclear.
Within the DC film universe Steppenwolf has been defeated and the post credits sequence of the movie seemed to set up a future League confrontation with Lex Luthor, not a furthering of the galactic plot of the movie that had just wrapped up.