In Dark Realm run around the hut and you’ll be fine. He will quit Dark Realm after some time.

No more Mezuki in the twilight mission "the bloody tainted samurai" late nerf ? (comparison from the last chance demo) rather disappointing

dual axes are great for this boss you can block almost every attack with no stamina loss

Blocking the yokai realm-spawning black orbs is a really bad idea. If you are a low level and not using one of the few very high block weapons, two will break your guard.

That glowing rock on the left if you enter the arena can be destroyed by Mezuki and it wil fill up your entire Amrita Gauge.

His burst attack is easy to counter once you get the hang of the burst mechanic. If in doubt, use the hut to wall Mezuki off to give you time to heal or prepare for an opening.

Giddyup

Found this guy pretty easy using hit & run tactics with odachi high stance, switching to low when entering the yokai realm to save ki. Making sure to burst counter all opportunities. Sure the same thing will work for other weapons.

does he have a voiceline or not, i've been trying to get him to speak for a long while now