Counter chicken wing with either the almighty :u:+:lk: or standing :hk:.
As for what you should be doing vs. Fei, I can’t answer questions like that at length, because once you get past a fundamental, groundwork strategy that applies to multiple characters, you really have to fight the guy controlling the character, not the character itself.
I mean, you know, do what Chun does best, for starters. Throw lots of :lp: fireballs without being rhythmical about it, and throw standing :hk: and :u:+:lk: in there to discourage the stupid chicken wing. Then, when you’ve got the guy demoralized, start with the real meat of her game: pokes and throws.
After that, you gotta figure out what kind of player the guy is, and go from there. Like Mike McDermott says in Rounders, “the key to the game is playing the man, not the cards.”
I will add that, given the low state of competition in this, the HDR era of Super Turbo, poking and throwing will be more than enough to win vs. 75% of your opponents. Most players (that includes most people who post on these forums) are indistinguishable from one another; I don’t know where these kids learned this crap, but the prevailing modus operandi is something like jumping back and randomly pressing buttons, hoping the other guy will make a mistake on which one can capitalize. (I mean, I am fighting turtle Cammys, for f**k’s sake. That is how low we’ve sunk in this game.) Players who play like that usually fold under pressure, as they never do enough actual fighting to develop the nerve it takes to counter a poke/throw assault.
Hell, I’m not even quite sure why I still play this game. I think the Japanese players are the only ones keeping me interested. Fought YuuVega’s Dictator last night, what a refreshing match that was! Just like old times (back when people actually fought).