why not
you could add different weapons in swordbattle like the paladin, scythe, and sabre
i feel like adding anything pvp related to the 2 games would drastically change the game and not in a good way
realmz being on this forum is a swordbattle crossover
but maybe adding a skin from SB and one from realmz would work, but its so little it doesnt really matter
there has to be a better way to do a crossover because the games are so different