OK, so there's still no gameplay trailer yet, but I do enjoy the humor of these four characters in Suicide Squad: Kill the Justice League. As mentioned before, Brainiac has control of the League and its up to Boomerang, King Shark, Deadshot, and Harley Quinn to take them down.
Today at DC Fandom, Rocksteady released a new story trailer showing off more with some appearances by some of the League members. Most prominent was The Flash followed by quick shots of Green Lantern, Superman and Wonder Woman. The Batman is only seen via his Batmobile, but I wouldn't be surprised if he escaped the mind control of Brainiac some how. Why? Because he's Batman!
Anyways, here's a nice 3 minute video showcasing some of the characters and some NPCs you'll run into along the way.