It’s a matter of play style, and I’ve found that the more I play Chun, the way my play has evolved has mostly concisted of “Well, I should probably stop doing this because it’s not worth it”.
This concerns every part of her, don’t throw fireballs where they can jump over them onto you, don’t use sweep more than st.mp/st.hp, don’t use 50/50’s unless it’s a kill situation/mid screen where switching sides doesn’t have a big impact etc.
The less openings you leave for others to take advantage of/get a lucky break with, the more you are forcing them to actually outplay and deal with the simple things that make Chun strong.
Against Akuma it’s about establishing the fact that when you are spaced correctly you can walk in on him if he jumps back, and you can trade well with air fireballs with c.hk. At the same range if he jumps in you can meet him with j.hp/air throw which will trade/beat him out of he does ex hado/demon flip or jumpin attacks. If he tries to play footsies you can zone him with st.mp/b+mk and c.hk.
Focus backdash is completely safe against all of his pokes on max range, even if he cancels into u1, does c.mk x hk tatsu or whatever. If you have U1 and you expect him to use c.hk you can focus backdash it, then during his ultra animation you have enough charge time to use yours directly after your backdash finishes.
OS Block/LK Hazanshu is a good option against his demonflip okizeme, you probably have to training mode the timing down if you don’t have any Akuma’s you play against on the regular.
It should be possible to OS Block/Backdash as well, by inputting back~back very late on your wakeup so the first back input = the first frame of standing, but at least for me that input is difficult to get down consistently. I should training mode that some more.
What these option selects do is if he does palm you block it, but if he uses the other options they come out.
With LK Hazanshu you block palm, punish throw and get air reset by demonflip kick so you can focus backdash out.
With OS Backdash you block palm, backdash throw (can probably ex legs punish), and backdash the kick safely.
In general I feel Chun has better options than plenty of the cast against Akuma’s mixup game.
Like I said, it’s a matchup where Chun needs to know a lot of things/do more than Akuma, but that doesn’t mean it’s horrible because of that. When Chun does all of those things it becomes much better than general concensus claims it is.