Kung Lao (I forget the variation) and Kano (also forget the variation). They're probably the most difficult for me to try and overcome online.

Scorpion (Inferno) and Kung Jin (Bojutsu) are the most annoying.

-Kung Jin is annoying to face, though I've gotten a lot better at reading his moves
-Liu Kang. Unfortunately I've ran into a LOT of these lately(spamming the 4,4,4,4 combo +flying and bicycle kicks with fireball zoning ugh)
-Shinnok zoners can be ridiculous to face as well for me, especially if im using a character with no teleports like cassie makes getting in for the punish a bitch and a half to execute lol.

I wish I saw some more Shinnoks online. Don't think I've ever fought one! Starting to see a lot of Liu Kang now.

I play Shinnok but I'm on xbox one. I made a lot of people hate Shinnok. They think he is cheap now and before he was patch.

Kenshi always kicks my ass. Except for this one player who sucked with him and ragequitted on me once they realized I was winning. That was my first quitality and it was satisfying.