Basically, you wanna turtle the crap out of this match. This used to be a bad thing to do, because Chun had no answer for repeated Chicken Wings in the corner (J.Lk has always beat it cleanly), but now the Chicken Wing trap, while still effective, isn’t quite as deadly against Chun. Playing the mind game here is favorable compared to how it used to be.
When you’re not in the corner, do a lot of C.Mk and Neutral J.Lk, mixed in with Kikokens - especially for AA. This will give Fei a hard time knocking you down, hitting you with Rekkas, etc.
To really handle this match though, you need to have a grasp on Fei’s corner traps. I’m not exactly a great Fei player, but I’d say the corner mind games go something like this…Fei will come up on you and do one of two things:
Rekka x2, wait.
After Chicken Wing, he can either do instant Flame Kicks, another Chicken Wing, or go for the throw.
After Rekka, he can also go for the Flame Kicks, but he can also start up the Rekka pressure again, he can do the third Rekka punch (which knocks down) incredibly late, Chicken Wing/J.Hk, or he can pressure you with normals.
The point of both of these are different: Blocking a Chicken Wing is intense, cos it puts Fei right in your face, but Rekkas are different - the whole point of Rekka x2 is that if the Fei player does it right, he’ll wind up just outside of the range of all your normals.
The good news about this guessing game is that you have three or four options which shut down several of his:
Neutral J.Lk: This will beat Chicken Wings clean every time, and almost always beats Feis other jump-ins. This will also peg Fei on the way down if he went for Rekkas. DON’T use this option after a blocked Chicken Wing, because he’s close enough to just go for a Flame Kick which will hit you right out of the air.
FP Kikoken: This is useful because it will hit Fei out of his Flame Kicks. This is about the only way to handle Flame Kicks safely. You could, of course, just wait and see what he does, but Fei would love it if you kept waiting and watching - that way, he can just sit there and pressure you forever. Use FP Kikoken because it has the shortest recovery time, and will reach Fei the quickest, making it decisively the most useful version of the fireball in this situation. Fei’s counter to this will be the Chicken Wing.
C.Mk/C.Hk: There is a use for normals in this guessing game, though: Your normals have a high probability of beating Fei’s, and as opposed to the FP Kikoken, you’ll have ample time to act if Fei does the Chicken Wing and you went for C.Mk. I have C.Hk in there because if you can knock Fei down, you can start putting the pressure on him, but I recommend using this one sparingly since it’s really unsafe in this situation.
Throw: You can use this against Feis with bad Chicken Wing timing, but the main importance of this option is of course to Counter or Tech Fei’s throw attempt.
Basically, you have the advantage in this guessing game as your options are safer, but Fei has the advantage that if he guesses right, you’re gonna eat a crapload of damage.
The last aspect of this match is rushing down Fei. You can rush Fei down, but be careful - if there’s one thing I learned from playing Jumpsuit, an EXCELLENT Fei player, it’s that Fei will lay your ass flat if you are not super careful when trying to rush Fei. It might seem risky, but it’s important to at least try to incorporate a bit of offense in this match, as you’ll be hard-pressed to kill Fei with nothing but Fireballs, C.Mk, and J.Lk. You gotta throw in some throws!