I don't know if this is a PC/M&KB-exclusive problem, or something that affects the game as a whole, but with the way the game seems to "cache" my inputs makes practicing the timing of abilities/parries/cancels all the more difficult because of it.
Even in the Dojo with zero latency/ping problems, it's a hair-pulling nightmare to practice parry timing because of the cached inputs. I'll try to time it for one hit, whiff and take the hit, and think "alright I'll get the next one", but thanks to the whiffed parry being "cached" it ends up going through the instant I'm no longer staggered, meaning I've wasted a parry and am in "recovery frames" by the time the window for the next parry opens up. Even against someone with slow telegraphed attacks like Makutu becomes a challenge to parry because the cached inputs throw the timing off.
The parry window was already wickedly tiny, but this just makes them nearly impossible to pull off even in a controlled scenario, let alone in a proper match with inconsistent latency.
I have the same issue on xbox so I feel your pain.