Fan Casting Superman Back to the Future

After defeating Mr. Mxyzptlk and the Anti-Moniter, Superman has to stop a new variant of the Anti-Moniter that is destroying the multiverse, but since the Justice League is retired and mostly dead him and Dick Grayson's Batman go back in time to get the original Justice League. Once they get to the past, they are attacked by villains such as Sinestro, Gorilla Grodd, and Lex Luthor. They manage to defeat those villains but eventually have to take on Darkseid, but luckily they have the help of Bruce Wayne's Batman, the original Clark Kent, and Aquaman. The movie ends with Wally West sending them back to their time but when they get there it has been destroyed by the Anti-Moniter and so they go back to the past and decide they need to stop the Anti-Moniter from destroying the multiverse, and so Clark Kent, Dick Grayson, and the past Justice League go to another universe which just so happens to be the Teen Titans Dc/Marvel universe which just so happens to be the last remaining universe. So now the Justice Leagues from the Dc cinematic universe and the DCU, the Avengers from The Underworld Universe and the Marvel Universe, and everything in between are all in the same universe alongside the Justice League, Avengers, X-Men, and everything else that were in that universe originally.