Tested with the entire cast in the variations that would make sense to be able to punish. This means I didn't test e.g wrestler Jax or dualist Liu and so on and so forth so some obscure punishers may not be included in this list. Every character in the game bar Mileena can punish the overhead sword, certain characters can punish the low sword depending on the distance.
Subzero - F4 punishes OH, Slide all.
Mileena - Can't punish anything.
Cassie - Punishes OH with IAGS, can't punish with B1.
Jacquie - Force rush, Gauntlet strike, gunshots all punish OH and Low sword.
Kung Jin - UF Instant air divekick, punishes OH sword.
Kung Lao - UF Instant air divekick, non-tempest EX spin.
Scorpion - Ninjutsu F2 punishes the OH.
@Vagrant "Scorpion in hellfire can do F3 FBRC f3 spear. "
Kitana - [] Boost punishes both, throat slice the overhead and the low only if the low is done at close range
Kenshi - Flurry, both.
Jax - Bugged, he gets almost no pushback on block whenever he blocks the overhead, only one in the entire cast, punishes overhead with 11/dash punch/DP, DP punishes a close range low sword too.
Shinnok - Shoulder punishes both, F2 punishes the OH.
Kano - IAB
Johnny - F3 punishes the OH, shadow kick and flipkick punish both, stunt double gets a full combo punish.
Eren Black - Slide and command throw punish the overhead, the low is safe.
Goro - Chest lunge
Liu Kang - Low fire, Dragon kick punish the close low and OH at any range.
Ermac - Soul charge/IASC punish both.
Reptle - Slide and Dash punish both.
F/Torr - Boss toss punishes the OH and the close low.
D'Vorah - Ovipositor punishers a close/mid range low and OH.
Raiden - EX Shocker punishes both, Superman punishes OH and Low unless former's done at max range.
Quan - Rune punishes the OH, can't follow up with trance because of awkward distance, B2 trance also punishes but not B2 rune also because of awkward distance where both close and mid runes whiff.
Sonya - F2 punishes the OH sword. Super tight window.
Tanya - F2 and EX teleport in all variations
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