I was wondering how I could one translate "the bearded man", in the same fashion as the Straw Hat Luffy (in one Piece) "Mugiwara" ? I understood mugiwara means "Straw" but people seem okay calling him by just this word, and not "the straw hat man". Thank you very much!
As simple as ひげ／ヒゲ can work as a nickname, although I believe most real people with beard do not like to be called in this way. In fiction, especially in old fictional works, many people have simple nicknames like ヒゲ, メガネ, アゴ, etc.