Hazama's assists are a bit lacking, so you'd generally want him on point. You'd want a partner that helps him cover his spacing or zoning issues while being able to convert off from his 214x and 236x specials.
Becomes a powerhouse within resonance blaze and can get 10k+ damage alone with the proper combo routes BUT be wary of Hazama's limitations. NONE of his assists makes him move forward, so take note of this when you go for cross combos.
A few examples that can complement Hazama's game plan are: Nu-13, Gordeau, Carmine, Hyde, Es, Blake, Ruby, Orie, Yosuke
Overall, try to find partners that help with Hazama's lack of spacing and to cover his approaches while being able to help with his combo routes.
Tips and Tricks
The first hits of Hazama's 214A and 236A can be pushblocked, forcing him to whiff the moves and have an assist cover for him. Jagai itself does have a small gap within where certain characters can jab him out, but be wary of Hazama players who will try to do Jagai > 5A+D which is a reversal.
Try to anticipate Hazama's limited chain routes and anti-air accordingly. He has a few options in the air once he commits to a chain, mainly: j.BBB, j.A, and j.C, which the latter is one of the safer options Hazama can do if he decides to cancel a committed chain dash.
Be wary when using cross burst if you're caught by 236C - Hungry Coils. Hazama is invincible for the entire animation once he starts reeling in the caught character. He's also able to immediately do 5A+D if you try to punish him while still invincible, so try to wait accordingly when punishing for it.