I just discovered that Chinese fans call Giorno 茸茸 (róng róng). From my limited reading abilities, I have gathered that it’s because the character 茸 sounds like “Jo” when pronounced in Japanese. Fans settled on this nickname because 茸茸 means fluffy/downy. Someone made a drawing of Giorno using a lot of yellow, and everyone thought he looked like a soft yellow duckling…
And some people call Abbacchio 茶哥 (chá gē) which is “tea bro”, and I think that’s wonderfully deep and poetic