Cody can edge out Akuma from full screen in a fireball war because of sliding under Red Fireballs. However, as soon as Akuma gets EX meter, the threat of an EX Demon Flip at any time makes the lengthy animation on Bad Stone much riskier. This is accentuated by knock downs being so devastating, because Cody has no options to escape the Akuma vortex.
When knocked down, Cody must simply block well. Using EX Zonk is very unreliable against Akuma's mixup, and most vortex options are jumps that will automatically safe jump the slow startup of EX Zonk, anyway.
This matchup is best played with a passive aggressive style. By staying within mid range, Cody has a very effective way to deal with with both ground and air fireballs. If the Akuma player is using mostly ground fireballs, keeping a Zonk charged easily counters that. However, it is more likely the Akuma player will use more air fireballs, rather then ground, especially if Cody has the threat of U2. In this case, reacting to an Air Fireball with EX Ruffian Kick is a great punish that scores Cody a much needed knockdown.
For anti-air, b.MP is not as strong in this matchup as in others. It is difficult to time b.MP to beat Demon Flip options cleanly, both because of the variable timing of the attacks (Demon Flip Kick stalls him in the air), but also because the options have such high priority. Due to this, it is preferable to anti-air Demon Flips with HK Ruffian Kick (if they can be reacted to quickly), otherwise, a simple c.MK is a good alternative from most ranges. If Akuma Demon Flips in deep, an early c.MK will slide Cody under Akuma. If he Demon Flips in too shallow, a late c.MK will anti-air him reliably. Only Demon Flips spaced deep, without being deep enough to c.MK under completely are safe against c.MK.
Once Cody gets a knockdown, it can be hard to maintain pressure between the Dragon Punch and Teleports. But a few good reads makes Akuma lose life quickly. Also, Akuma's lower stun rating means he gets stunned in 2 solid HP CU combos. If a Teleport backwards on wakeup is anticipated, jumping in and option-selecting a t.HK will put Cody in range to punish either strength Teleport with an EX Ruffian Kick.
If you see Akuma do Demon Flip, nj. HP usually beats it clean.
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