Let me be clear: Yasuke is a figure who has a lot of story and gameplay potential in a Japanese-set video game. He'd be a fantastic character hack n slash along the lines of Dynasty Warriors or even a commander in a tactics game like Kessen, if you want to be generous with the privileges his status may have given him. Yasuke would also be a welcome addition to Assassin's Creed: Shadows as an NPC, an ally to our hero as a representative of Nobunaga.

However Yasuke being the protagonist in an Assassin's Creed game-- a series based on stealth and espionage-- removes any plausible deniability for him. For anyone NOT to immediately know who the 6 ft African man is makes the antagonists foolish.

Let's take the video of Yasuke straight up annihilating dudes in the middle of town in broad daylight. I understand the character is meant to be more combat-oriented compared to Naoe, but that doesn't mean he should be completely conspicuous. Does he not think that the people present might be questioned later? Is he counting on them not noticing his skin color?

Anyone killed by Yasuke immediately paints a target on Nobunaga. There were so few African slaves in Japan at this time, Yasuke literally got to where he was by being the first black guy Nobunaga ever met. He was purchased as a novelty. What if one of his future targets is allied to Nobunaga? If he learns people are getting killed by an African Samurai, might he not approach Nobunaga and give him an ultimatum? "Hey buddy, you gotta choose: my money/resources/power or your pet".

He's ludonarrative dissonance as a character.

If Ubisoft wanted to introduce a non-Japanese samurai character, could they not make him Chinese, Korean, or Ainu? Maybe he got the armor from killing a Japanese samurai. Ubisoft apparently doesn't know the difference between Japanese and Chinese architecture so maybe that's not diverse enough for them.