I've encountered this bug multiple times, it seems to occur randomly where a mermaid sim doesn't use their swimming animations but rather use humanoid swimming animations instead, which looks very off.. The issue seems to resolve itself after getting out of the water and in again. I don't think this has anything to do with the CC i use since most of what i use is cosmetics for the sims themselves and nothing related to mermaids or swimming at all. Not sure if anyone else had this but just thought i'd report this and see.
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