On a slightly different note, does anyone here read manhwa?

Yes

I need a secondary opinion because the more I read, the more it feels like some of the groups localising them use machine translation (or non-fluent people). Things like constant misgendering, regular changes to name spelling (for both people and locations), attributing things said in the past to wrong characters and more are pretty much something I expect rather than a surprise at this point. It’s distracting, sloppy and, at times, pretty annoying.

Assuming you mean scanlation groups, I absolutely feel the same. I often just don’t read ones like that because of it, because it’s hard to make heads or tails from it. I think it’s a combo of MTL and non-fluent speakers. Stuff like misgendering or wrong attribution is very MTL-like, but a lot of the bad grammar, spelling errors and bad punctuation feel more like things from someone who doesn’t quite have a good grasp on English (can be MTL, but MTL is pretty capable of making well-structured sentences at this point).

Just in general I struggle finding good scanlation groups for manhwa (or sources even). Either they have poor translations, are behind paywalls (surprisingly common. Many even use their own stupid coin systems) or both. I often resort to only reading officially translated manhwa (officially or otherwise).