I'm not an expert so this is probably wrong.
Based on my experience you want to keep him at a distance. not too far, just far enough that he cant get you with that horrible grab attack. If he tries the air grab either duck or, preferably, 2B to smack him out of the air (follow up with whatever works for you). watch out for his long range persona attacks. you can block them pretty easily but they can follow up with air grab while your still blocking the persona attack.
Again, I'm no expert so that's probably bad advice. hopefully someone who knows what their doing pops in here soon.