The Minogame's Protection legendary amulet in Assassin's Creed Shadows increases damage for empty Armor slots, so Yasuke is better off naked.

In Assassin's Creed Shadows, Yasuke's name was originally Diogo, and the process of changing his name dates back to the history of 16th-century Japan.

Having the ability to not only block, but Parry red attacks as Yasuke is a game-changer for combat. This makes the Protector's Armor the best early-game armor for Yasuke. There is really no need to find another Legendary Chest Armor piece until much later in the game.