I made the mistake of gifting a wrong shirt to a resident. I tried to talk to Isabelle about it, and it thre resident briefly changes back to its original outfit, but the next day the horrible sweater is back. Its been going on for 12 days now.
One time she even switched to a Nook shirt rather than her original outfit. That was weird.
Anyone know the correct routine to get rid of unwanted clothing?
Try gifting them a new one that you like better. It worked for me when Julian was wearing this bowling shirt I hated. I gave him a new shirt and haven’t seen it since. I don’t know if this 100% works though because if they don’t like it they may not wear it.
Unfortunately complaining to Isabelle only removes the clothing for one day - I'm not sure why exactly! As for why she switched to nook shirt, I think that happens when you complain to Isabelle when the villager is wearing their default outfit.