Sorry if this is a duplicate, I made sure to search through issues about the Piglin and didn't find anything related to this.
Even if a Piglin spawns left-handed, giving it gold will still cause it to look into its left hand, as if it were a right-handed Piglin. Happens for both sword and crossbow Piglins. Since the Piglins are supposed to look like they're gazing at the gold, I'm lead to believe this is an unintentional side-effect of some being left-handed.