I think that law will lose so that BB gets 3/4 poneglyphs.
but I also think that law will somehow survive the fight and run away, since we still need him to later sacrifice himself on someone using that hidden power of Ope Ope No Mi.
So in this arc, if Luffy and SH will ally with vegapunk and face CP0, and Law will face BB, I wonder who kidd will get to face wherever he went.