Will Sephiroth be redeemed?

They'll call him Ratdog

Which was a necessary step to change fate. We still don't know what Sephiroth is up to.

what's a fujo?

Everyone has already worked it out. Nomura's problem is that he retroactively rewrites plot elements when fans figure them out in an attempt to keep things surprising.

This is deliberately left ambiguous. However after the Jenova Life fight it's Jenova herself who calls Cloud a puppet, not Sephiroth.

then why did they already fight?

I can't wait to fight the final boss with Zack, Sephiroth, and Rufus.

he always had cat eyes in the og game ... but why he has a gay boner for cloud is a mystery or rather its nomura self insert into sephiroth... also the black wing was never a thing on human sephiroth either.

The Sephiroth we fight as final boss in the remake is not tge real one. Real Sephiroth only appears in the very last cutscene with Cloud when he asks him for help.

Just to fuck with Cloud. He easily disarms him when they recreate the final fight.