If rumors are to be believed, then the upcoming Superman Vs. Batman or Batman Vs. Superman movie will feature an older Batman teamed up with Henry Cavill's younger Superman. But before the movie was ever announced, it turns out that Beware The Batman producer Mitch Watson pitched an idea for a Superman and Batman cartoon show.
In an interview with SciFiNow, Watson revealed that the Superman Vs. Batman cartoon show would have featured both Batman and Superman at the beginning of their careers. From the description, the series would have focused more on Bruce Wayne and Clark Kent, who become friends without realizing that they are both superheroes. In their superhero identities, Batman and Superman hate each other.
Eventually, Batman and Superman realize each others secret identities, and they make up and end up living in the same building. The tone of the show is described as being much lighter than Beware The Batman. Watson said, "It explored two guys in their early 20s as they were becoming heroes. That was the gist of the story."