Ryu wins this match 6-4, and I believe this is not really one of those “loser gotta be amazing to make it 6-4.” It seems some basic Chun stuff can give Ryu a lot of trouble. Anyway, let’s start from the beginning.
Ryu will not throw SRKs if Chun does not leave the ground, as her normals are hard to hit with it. A too early or too late SRK will miss cr.forward, and other attacks often whiff. If you want to try something, it would be getting to the range SRK misses a neckbreaker, and hope he does not recognize it and does a jumping strong x3. Don’t try it against good Ryus.
Speaking of jumping in, it is important to learn how to cross him up. Then get to that range and jump with short, so if the Ryu player is holding the joystick back, he gets pinned down and is forced to block. If he tries a lat hadouken, he will get hit on the head while still grounded and eat a small combo. Avoid jumping before forcing Ryu to throw hadoukens. There are two main ways of doing it: the first one is keeping up with the projectile war so that he gets used to throwing from 3 to 5 projectiles before forcing you to block or jump. As he gets trained into throwing many of them, you can jump when it is appropriate. The other one is to get him in the corner and apply some pressure, such as meaty cr.forward, cr.foward, jab kikouken, then walk up a bit and attack again. Something like this. As soon as you give him a little air to breath, faint as you are walking up then jump. Ryu’s most reliable way of avoiding Chun’s pressure is to sneak a red hadouken between her pokes, so odds are he is looking for it. Or jump as soon as he recovers from blockstun if he is likely to throw a hadouken right away.
You must learn Chun’s punch into fierce kikouken or lightning legs combos, so you can jump and either stun him or get him almost stunned. That way, in most rounds you guess right a jump in, you will win. If you have not attacked him recently, you can try a combo ending with cr.roundhouse and try a throw, overhead or bait a move as he wakes up. Dizzy, peace out.
Chun Li recovers instantly from jumps if she uses a head stomp. It can be hard to throw her if you jump forward, whiff a headstomp and throw the enemy as soon as you land on the other side. Just don’t get into the habit of doing it every time: you will miss opportunities of finishing matches right away with her dizzy combos.
When Ryu is wondering what to do or waiting a move, try just walking forward, and take note what is his default action. Just by walking forward to get in range to use your vastly superior pokes and harass him. Ryu can not compete with Chun’s ground game, so he will eventually try a walk up sweep/forward or sneak some red hadouken in between your pokes. This is why Chun must not attack relentlessly, but throw get back just a bit to give him room to whiff or leave standing forwards and roundhouses so as to beat eventual hadoukens or tatsus.
BTW, as Ryu is often waiting for a whiffed attack so as to counter-attack, and Chun is quite fast anyway, have the walk-up strong throw in mind. That does damage similar to an SPD if the enemy does not soften it. Also, after meaty attacks and blocked air moves, always consider it, depending on the enemy’s style. Reversal-happy Ryus have trouble with Chun and she has pokes with descent range and a fast speed: just let him whiff a reversal SRK and throw.
Check this also. It is in HDR thread but I had written it based on ST alone. And remember this: “If Chun can not dominate Ryu and force him to take risks, she has no business expecting to win.”
In addition to that post, know that in ST Chun can keep Ryu guessing on wake-up with her neckbreaker. From point-blank range, it switches sides and he gotta block the other direction. Some players also do not know you can block it while crouching, so they sometimes get hit low.