Strangely, I find that most of my damage against Hazama comes from the air B lobelia. It's an excellent answer to his straight ground chain.
But just in general, when you're both at distance, air moves are the way to go. Even if you're at full screen on the ground, if you summon anything he could always just dash in once and then chain you for a nice juicy counterhit. And obviously him at 50% meter should make you stop ground summons/fireballs entirely. The air's a great place to summon frogs, punish a chain whiff with a B lobelia, or just start chucking A lobelias if he gets jump-happy. Also, if he does hit you out of the air, most likely from his jumping straight chain, at least it's not going to lead to a full bnb combo.
Also, I'd be cautious of using 6A to counter his chain pull-in advances. It does work, sometimes, but that move in general is just so flakey. Far more often than I'd like, that move just doesn't feel like beating his jump attack, and I'll eat full combo for it. If you're at a position where you know he can't get behind you, just go with 2C as soon as you see him pull himself in. Works every time.
And yeah, all in all, this a pretty long and boring matchup. Time usually settles it.