FF7 NES

Isn't space only an issue if you want to make physical copies (even then you could in theory make your own mapper)?

Space yes, memory no.
This rom already uses custom mapper in fact.
It's the memory limit that's something you can't bypass. It's a hardware limitation.

Are the weapon fights in this

Romhacking mentions optional superbosses so I think so

I thought it was made by Chinese bootleggers because NES was still the most popular console in the third world at the time