Hmm, well going through xmog collections...
some of the "katanas" are okay, the hilt's generally too long but they could be wielded feasibly
Everything else seems too big, too heavy or just biomechanically unfeasible. Only looking at swords/axes/maces/polearms tho cause that's all that's in my wardrobe.
But yeah as i said, it doesn't matter cause the game isn't trying for realism... in like anything. In fact having realistic weapons would probably do the game a diservice