Feint cancels on her c.M and s.M are super clutch imo… those moves have awesome startup and hitboxes, lots of active frames too, but are so bad on whiff. Some math from the bible:
s.M startup 5 frames, active 2 frames, then 2 frame gap, then 3 active frames, then 19 frames recovery
c.M startup 6 frames, active 7 frames, 16 frames recovery
for comparisons sake, Wesker c.M is 8/5/14
Feint cancels have 3 frames startup - cancel with S on the 4th frame, 5 frames of recovery so 8 frames total
So you can effectively reduce the recovery of something like c.M from between 18 to 24 frames to 8. That makes c.M in particular one hell of a buff move… unfortunately hit confirming out of feint canceled c.Ms is (imo) very difficult. s.M is somewhat easier, the way I do it anyway… at first I was running around holding S but now I do it with qcb+L+S so I can cancel whenever I want… it takes some getting used to doing the motion fast, buttons held down at the end… if you let go of S during the 3 frame startup of the feints, the cancel won’t happen. If you use the “hold S” method they get way way easier and its pretty easy to find places to hide the S input as X-23.
More math (this is old shit anyway)
stand H into L feint on block - +7
stand H into M feint on block - -4
both of them become substantially safer if they advance guard, making stuff like stand H xx L feint wavedash c.M airtight and stand H x M feint c.L pretty good. only problem is, stand H pushblocked into M feint is not ambiguous unless you are in the corner. midscreen it is hella easy to block. To get the really tasty left/right mixup out of a stand H when you know they are blocking, you need to call a lockdown-type assist (Akuma tatsu, black hole), set your spacing and then do the M feint so that you recover where they are standing as the assist ends. Done right, neither of you will know WTF is going on and you should be able to hit confirm into a good combo or setup a crossup talon dive.
Other news - her command grab is pretty crap. I keep meaning to see if it is super cancelable on whiff, though…
Method of dealing with the Hammer - bait, punish with dp or qcf super. Up close you need the instant invincibility of Rage Trigger (frames 1 to 19) but you have to watch for dumb shit like Dante falling out early because the super doesn’t carry him properly. From further out use Weapon X (frames 6 to 64 invincible)… too bad raw supers can’t start DHC glitches
Also, much thanks to whoever posted that c.H beats Tron assist cleanly. It certainly does, but the timing window is pretty tricky… too early and fire will punish the recovery of your c.H, because apparently only the active frames are short enough to go underneath. Too late and you have to block the fire.