i had same experience, but probably we both got lucky since people have trouble with him

spear that trusting* (Loaded Spear Thrust Type)

So I'm not much better off than you equipment-wise (don't even have the feather, but I've got my second health and attack upgrades). You can get at least that plus two more minor bosses done before you reach this guy. I'm guessing your attack upgrade is from Lord Gyoubu, so I'd recommend now placing the bell at the buddha statue in the temple and doing the Hinata Estate area. Completing that should net you enough extra necklace beads and a memory, which makes it easier. For actually beating this guy, took me a bit, but the way to handle it is to double-tap the deflect button. If you press and hold to deflect his first strike and block the second, you'll keep taking chunks of vitality and posture damage. Instead, once you've got the deflect timing for his first draw attack down, every time you deflect it double-tap the deflection and you should parry his second strike. He doesn't get any more inventive (not really) in the second phase either, so once you've handled that he'll fall.

Hold down your sprint button and run in circles around him, clockwise. Eventually he will sheath his sword and do a devastating attack that definitely won't hit you. Attack him once from behind and run away. Repeat until his health bar is empty.