One benefit of cl HK outside of frame trapping was it quickly shut down Dhalsim’s teleport mixup in almost every situation except the meaty knockdown -> EX fireball setup. Since it was a proximity normal, he couldn’t really “cross you up” (this applied to other crossup tactics from other characters as well like Honda’s reversal buttsplash). Even trading was in her favor, so the fireball itself wasn’t a threat as long as she was standing.
Now it seems that air grab is the most consistent way to deal with it in SF5 without thinking too much about being crossed up, but you still have to wait a bit longer and if doesn’t teleport near you, then you would be stuck in the air if you attempted this without making sure he’s near you first (i.e. reacting purely to the teleport startup animation). B+HK isn’t as effective in this situation since you still have to pick a direction.
I came from maining Ryu in SF3 and most games before that (Chun was more of a secondary then) to maining her full-time in SF4 and I will be maining her again in SF5.
General:
The main thing with Chun is your primary form of space control will be from the range and dominance of her normals combined with her fast movement speed. You’ll be mainly annoying and whiff punishing the opponent with pokes from the mid-range (F+MP, st. MK, cr. MK, sweep, etc. St. HP reaches far, but it isn’t nearly as fast on startup as it used to be so it’s not really abusable). White chip damage for normals also helps in piling on the pressure since Chun Li’s are pretty good.
Then the opponent who can’t out-poke you usually gets agitated by this and tries to either jump in or back up and throw fireballs.
-If you’re looking for the jump in, then anti-air with something like st. LK, B+HK, B+HP, neutral jump HK or air grab… use st. HP or st. HK if they are farther away. Knock them out of the air and get ready to harass them on the way down.
-If they want to back up and throw fireballs, I’d mainly throw my own FB to neutralize the fireball and build meter or neutral jump over it and slowly inch forward to either make them back up more or get into a more threatening space where I can go for a cr. MP (to go under the fireball), jump in attack, or super right through it if I have the meter. In V-trigger mode, her B+ HP also neutralizes single-hit fireballs.
…The key vs. both of those tactics is to try to gain ground instead of letting them push you back with that stuff. She does a lot better with open space behind her.
If it’s an opponent who can kind of match you with pokes or out-poke you like Bison or Vega, you’ll usually do better moving into a closer range. Get them to whiff something or throw a fireball and move in.
Up close, again use her good walk speed and the dominance of her normals. Harass the opponent with her fast light attacks, st. MP and B+HP for tick grab and counterhit/frame trap pressure and convert those into combos when you get a hit. Hover in and out of the mid-range and their grab range and try to bait them in to pressing something bad so you can get a whiff punish. F+HK goes over low attacks and avoid throws while moving forward. DF+MK is just to wake up the opponent who blocks low too much. It’s slower than most overheads, so without covering it with a fireball first, you won’t be getting this too often without being stuffed first.
^ All this stuff becomes better when she pops v-trigger and converts into good damage on hit, so I expect Chun players will want to have that available WAY more often then having to resort to using v-reversal to get out of block pressure.
Special moves:
You asked about charge times. It takes a little under a second to have your charge ready… this is a lot faster than people initially think they have to do when they get into a charge character. In SF4 it was 55 frames (55/60th of a second), but it might be even less in this. When you master it, people often underestimate it and think that you don’t have charge and that they can do something stupid when really you’re ready to punish whatever it is they try. For SF5 this will mainly be punishing bad jump ins or loose pressure strings with EX SBK.
Her fireball, isn’t like the typical shoto fireball, it moves slow BUT she recovers from it fairly quick so she can walk behind it and use it as a mini-shield and then follow up with one of her ranged pokes or an overhead/low/throw mixup. Moving behind it to gain ground is it’s best use imo. Also, as long as you’re not too close, you’ll usually recover fast enough for an anti-air normal if they jump over it. It’s also still very good for zoning against grapplers and characters who don’t deal with fireballs very well in general.
You won’t be winning too many fireball wars with it, but still use it to keep the opponent from getting too much momentum from fireballs (and you gain meter just for throwing them)… you can always neutral jump over their fireball and reset the pace if they are starting to “win” the fireball war.
Holding a charge with down+back not only gives you access to both of her charge moves, but also keeps you firmly planted in the same position without moving backward. Remember that you’re still vulnerable to overheads though and sometimes you should move back a bit before throwing a fireball to get optimal spacing.
Lightning legs are a motion move now instead of mutli-kick input, so it’s quicker to pull off, but they aren’t + on block anymore (actually, besides EX legs and TK air Legs, they are punishable on block now). They’ll be mainly used for confirms off of her normals for combo damage instead of pressure. Use TK Air Legs if you want to pressure (people are saying they are safe and maybe even + on block). You can link into cr. LP after LK Legs and TK Air Legs on hit if you’re close enough to the opponent.
Regular SBK is usually just for ending combos. It has the most damage output of any of her special moves and knocks down afterward.
V-Skill is basically a different angled jump that travels a bit faster, but you can’t do any moves until about the mid-way point of the jump. I’ve seen this mainly used for crossup setups or to come down with Air Legs for pressure. It also hits on the way up and you can juggle afterward, but that hitbox isn’t that great imo (don’t use it as an anti-air lol).
Super:
It’s a motion move in this game (it fluctuates from charge to motion input in several games). Being motion means you still have access to it while moving forward, so confirming into it and going through fireballs with it will be easier. It’s 5f startup and travels about 2/3 of the screen in distance, so it can punish a lot of moves on block as well. It also can be juggled off of a lot of anti-airs like crush counter B+HP, crush counter st. HK, jump MP or many of her normals in V-trigger mode.
-I’m not going to go over frame data. I’ll just say that knowing it for Chun (as well as what was unsafe for other characters) was extremely beneficial in SF4 and will be very beneficial in SF5. If you haven’t been looking at gilley’s frame data doc, here it is:
It’s categorized by each beta and may change again in the final release, but getting the hang of it/memorizing it should improve the way you make decisions with her imo.
-Other than that, yeah just move fast and be annoying with her normals and you can get good mileage out of Chun if you choose to stick with her.
-Btw, The move that looks like Hazanshu from SF4 is her Senenshu overhead move (DF+MK). Other than also being an overhead, it functions nothing like Hazanshu. It doesn’t go over or through fireballs, it is not airborne at any point, so it can’t beat throws or low attacks (use F+HK for that). It’s just an overhead use to wake up people who block low too much. In V-trigger mode and on counterhit, I think you can combo into cr. LP on hit and convert that into a combo, but that’s the only thing special about it.
, oh ya, 
