I hear people do it and I seen a couple who has hand sewn their cosplays and looked amazing (though that was a long time ago and I'm not even sure where I saw that anymore).
But the only negative thing about hand sewing your cosplay is that it takes A LOT of time. When I first hand sewed my little sister's Hanabi from Naruto cosplay shirt (just the shirt!!!), it took me 1+ hour just to finish it without haven't to make it look .. well like you said "wonky and weird". Hahaha.
But if you have patience, I think it's definitely possible. :3 Good luck!