Some characters straight up can't do much about hellspark pressure (even if flawless blocking the second one). I know there's like a dozen videos out there that show these perfectly set up and meticulously positioned scenarios where the skulls hit way toward the back of your blocking hurtbox, allowing you to dash or jump out of the follow-up, but that's not consistent nor realistic the vast majority of the time.
I imagine Kabal is like Lao where you just have to hold dat. Liu, Sub, Geras (if flawless blocks), probably Nightwolf are chars that can shut it down on block.
I realize I'm hyperfocusing on only one element of his gameplay but honestly hellsparks are the only thing that ever gave me trouble.