User blog comment:Master Sima Yi/Assassinews 03-03-'13 — Assassin's Creed IV: Black Flag trailer and screenshots/@comment-26435037-20130303122111/@comment-1153722-20130303134720

Well, his face bears some similarity to Haytham's, in my opinion. Logical explanation would be that Haytham's mother Tessa was black-haired and of slightly darker skin, which Haytham would inherit from her.