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

Once I finally got to try out the ways of the samurai, I stumbled upon a Kofun that was tailor-made for Yasuke. Figuring out how to reach treasure within it was not only satisfying on its own, but since clearing one early on as Naoe, the ancient tomb actually turned out to be perfect training ground to get used to playing as Yasuke.

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.