To add to what TrueFist said.
Hazama basically has 2 BnBs you need to learn to play him.
His first is his mid-screen meterless combo, which can be summed up with stuff > 3C > ender. If you’re far it turns into 5B>5C(2)>3C>ender, if you’re close 5B>5C(2)>2C>3C>ender. There are 2 enders, one is 236D and the other is 214D~A. I generally prefer to end combos with 214D~A mid-screen since it gives you better heat and oki. In the corner you do a 214D (since it causes a wall-bounce) instead and continue the combo.
His second is his relaunch combo, which is basically looks like this 214D~C > 66 (for spacing purposes) > 6C > 66 > 5C(2) > 2C > 6D~A > 4D~A > 7 > j.8D > land > 623D > * 9 > j.6D~D > 66 > 6C > 66 > 2C > j.C(x5) > 5C(2) > 623D > 66 > Mizuchi
*(If you have trouble with this follow-up you can do 66 > 3C into whatever if you really can’t nail the rest of the combo, etc.)
This combo can also be started from air grabs, counter hit 3C and Houtenjin (ex. 5B>3C>Houtenjin).
Learn to use your chain and be unpredictable(!).
Know how your chain travels when you press the corresponding button (4D, 6D, j.6D, etc.) and don’t approach in the same manner (use all chain follow-ups, not just ~D. ~A, ~B and ~C are all useful). Watch pro Hazama matches (like with Buppa for example) and study how they use the chain. When you zone, remember to do a bunch of fake-outs with ~A, don’t always let them extend all the way (unless you think it’ll hit).
Also, don’t use the chain when they’re close or around mid-screen, since you can be punished for it.
Hazama’s pressure isn’t that scary or (too) tricky, but it’s relatively safe since you can end most pressure strings with moves that leave you safe on block (214D~A, 6B, 236D). Remember to be unpredictable and mix in jump-cancels, 6A, 236C, etc. keeping your opponent guessing. Remember that 3C(CH) and 214D~C can lead to big damage, so try and catch your opponents with those moves.
If you think the opponent will try and roll away from you after a knock-down, roll punish with 2A or 2B into (for example) …> 5C(2) > 2C > 4D~D > j.B > j.C(x1) > jump cancel > j.C(x5) > j.214B.
Try not to depend too much on Houtenjin as a reversal, because on whiff or block you are VERY vulnerable and you just paid 50 Heat to do so, in addion the prorate on Houtenjin is terrible if it’s used as a starter. Use it sparingly and learn to block and counter/escape properly instead. Gold Burst can be used as a reversal as well, if you hit the opponent with it then follow it up with 66 > 6C into relaunch combo.
To close off, this is my corner combo of choice from a standard BnB: stuff > 3C > 236D > 66 > 2C > j.C(x5) > 5C(2) > super jump > j.C(x5) > j.214B
Keep an eye out for when Dustloop comes back online again, they can help you more.