What I do find odd, is that when you look at the "temp" folder, you see a "battle.rpy" and a "campaign_battle.rpy". Does this mean they tried to implement it, but somehow failed and did not clean-up the remains of the coding?

Perhaps a patch can solve it. Or maybe modding. Or maybe it even works right now, I'm gonna try to copy the campaign replay to the replay section and see how it goes.