Most of the things that I have learned:
He has a low profile some times so 5p is pretty risky on run up.
Block high after the first 2(?) hits of the sword.
All sword hits while zappa is in the air are considered high. The ruff part is that he can land and jump and get a hit almost instantly.
Block the ghosts and wait for the 3rd one to be gone before running in.
Get the fk outa the corner when the dog shows up, any means necessary.
Watch for his 'running' overhead multi-hit thing.
Gotta be able to block those force breaks. I dunno the frame data but if you can block Venoms force break on reaction, then you can block his npnp, I guess you have to be used to seeing it. Also I think you get hit as soon as or right before the noise in some parts of the force break. It's very... fast?..
His DP doesn't give him 3 orbs anymore so I feel better rushing him down.
Standard combos apply, very easy to combo zappa.
Never ever jump vs Rawu(sp?). Ironically most zappas get reckless once he is out, so you can land some pretty juicy fafnirs and drain the meter because he is easy to combo, very risky but very rewarding; highly advise agaisnt it unless you are feeling your self.
As far as baiting zappa? I don't think there is much to bait outside of the ghosts. Maybe the vomit but that projectile is pretty serious.
Rockit works surprisingly well. The hitbox for HOS goes low then he jets forward, this dodges a lot of stuff that you think would hit. Depending on positioning, Rockit hits funny on zappas short profile hitbox. What I mean is that you might hit on the later active frames which allows you to maybe combo on a normal hit.
Most people can see 2hs as it is telegraphed. Most people don't block it because if they don't push a button, they take a little bit of damage, don't have to try and react, and they are even if not plus. Kinda like level 1 BRP. Yeah -1 on block. I only use it as a throw bait, but I use it wrong half the time and get thrown anyway. Then usual 2k -> 2s -> 2hs is nice and tricky and hit's from mad far away. That might catch people more; especially the pokers.
Lements of heavies. ~~