Some tech I have found out. Burst baits and crossup stuff. Will upload videos maybe. Some of the burst baits require precise timing to hit the edge of the character's hitbox. The first two require you to neutral jump, meaning not jumping forward, but only upwards.
The burst baits work on characters when they burst on the first hit. For other characters, MK a train can be used to armour through the burst if it is predicted.
Burst baits:
1. Corner only, works on everyone
stuff into s.MK NEUTRAL JUMP j.LP j.LK j.MP land s.LP
If you think they won't burst, you can do s.lp s.mk xx MK A-train.
This can armour through reacted bursts, you can jump and grab then afterwards, like in zeknife's video.
2. Corner only, works on everyone except Cerebella and Double.
stuff into s.MK NEUTRAL JUMP j.LP j.MK j.HP land, immediate j.LP LP cymbal clash for burst.
You can chain the last part into MK a-train if you think they're not going to burst. Alternatively you can jump grab after j.HP.
3. Corner only, requires sound stun, and works on everyone.
stuff into c.LP c.MP c.HP s.LPx2
If you think they won't burst, you can do s.lp s.mk xx MK A-train.
4. Midscreen, only works on Painwheel, Fortune and Valentine
stuff into s.MK j.LP j.LK j.MK land delayed s.LP
Other stuff:
Emergency brake crossunders:
stuff into s.HP xx HP Brass xx Emergency brake
If done right, you will crossunder your opponent. It requires precise timing.
You can also grab them instead by doing s.HP xx LP Brass xx Emergency brake (immediate) jump grab
Please note you can also do s.mk s.HP instead of just s.HP. I'm not sure how it affects the timing of the crossunders though.
j.MK whiffed crossovers:
stuff into s.MK j.LP j.MKx2 whiff, j.LK crossover
This works on everyone except big band.
c.MK crossup on incoming:
Simple but effective, you can use c.MK's big hitbox to crossup your opponent on incoming and combo with s.HP afterwards. Can also be used done into emergency brake crossunder to keep them in the corner.
EDIT: forgot to specify whether or not the burst baits were corner/midscreen specific. Sorry!