Same issue currently

Huh? I was sure that there was a whole discussion about that already, weird....

It only happens with one specific skeleton type. That happens because the creator of that skeleton race mod added incorrect arms model that conflict with pretty much everything.

The issue is already present in the original collection Kaizo/UWE.

I can't remove it as it is part of one of the core mods (can't remember if it is from Kaizo or another, I'll have to check, answering from memory here ^^ ) and I can't fix it as I'm not a creator and that no one made a fix for it.
There is even the possibility that it simply can't be fixed apart from removing that skeleton race entirely...

So, nothing I can do about it sadly.

EDIT: Some more info after I rechecked it. It only affects skeleton lionhead XT-MkIV and its variants, and that is an incompatibility with Yet Another Kenshi Nude Mod or YAKNM for short.

The issue has been known since at least 2021 but has never been fixed by anyone.

Therefore I guess that removing the nudity mods entirely (check the description for that) should solve the issue, but that is removing a LOT for such an issue. A workaround could be to simply not equip pants on that specific skeleton race, as they are already pretty powerful anyway.
But again, nothing I can fix myself and no one bothered to fix it in the past three years...