Bryan:
Bryan's DF2 and D2 CH confirms can present a problem for Feng's poke evasion. However, these are bad on whiff and can often be back kenpo'd in poke situations and KEN2'd on reaction. After Bryan blocks Feng's DF1, KEN always evades Bryan's 1+2 homing move.
Bryan's 3+4 is frequently evaded by QCF1 at anything but close range. QCF1 can even evade orbital near the end.
DB1 evades Bryan's jabs and magic 4 fine, since they have weak hitboxes. This and DB3 can be used to CH Bryan's homing moves while deterring these tools. If Feng is at +1, UF2 will SS Bryan's entire arsenal, trade favourably with his 1+2 homing, and CH his DF4 homing.
In the DB3 situation, be wary of Bryan's i12 WS3. Depending on side this can be unsteppable, and will CH launch you. This, again, whiffs on CC back kenpo. After blocking his WS3, you can kenpo the -10 string follow-up for a reaction KEN2 punish instead.
If Bryan is at substantial + frames, such as after you block his B1, UF2 no longer evades his jabs or magic 4.
Uses for punch sabaki: Follow-ups to his 1+2 homing can be option-selected with your own 1+2. If you bait an F4-1 whiff punish, you can parry that too, and his F1+4 unblockable if he tries to use it to close the round out. DF1 pressure is also very vulnerable to a sabaki.
Kazuya
Kazuya's DF2 locks down many evasive options and Feng doesn't get a great punish on it. Consider parrying it with 1+2 or iWS1+2. If you delay back kenpo so Feng hasn't stuck his right arm out when DF2 hits, you can back kenpo DF2 in most situations and KEN3 it on reaction for a launch. This will still evade most his pokes.