Mirror Universe gives this error when it attempts to load, forces mod to unload:
https://imgur.com/a/5pM3LeG

I get basically the same error when trying to load space exploration 0.6.x.
In 0.6 they added ammo (se-pheromone-ammo and se-bloater-ammo) that requires 2 fluid inputs, meaning MirrorUniverse now tries to make a mirrored recipe for it.
rusty_recipes.get_main_product(recipe).type apparently returns the ProductPrototype type, which is "item", instead of the Prototype type, which is "ammo".

I made an extremely bad and extremely minimal fix for my issue:
https://mods.factorio.com/mod/MirrorUniverse-ammofix

I also noticed that the mirrored versions of space exploration recipes didn't allow productivity modules.
I added space-exploration as an optional dependency to fix that.