Snyder's original plans for Justice Leauge (rumored)

I know that Kevin Smith said that in Snyder’s planned five film story arc, JL2 was supposed to have the League fight Darkseid’s forces in space with the help of the Green Lantern Corps, and that the planned fifth film would’ve taken place on the post-apocalyptic Earth we saw in BvS. I also know that Snyder said that Batman was supposed to die in the fifth film, but I’m not sure how the things mentioned in the OP would’ve tied into that. At the very least, it’s fun to speculate on.