Allow us to use Camo's across different game modes.

I think you already can, just press R1 and L1 to switch between zombie and multiplayer camos

You can although with the recent update it seems to be glitched, as trying to apply zombie camos while in multiplayer applies the multiplayer equivalent instead. (Trying to apply Green Tiger from zombies for example would instead just apply Red Tiger).

Yeah I believe you can,I haven’t played zombies can someone link some of the zombies camouflage please?

You can