(This helps for all difficulties)
(Knowing and learning this will 100% benefit for any future runners)
So throughout the game I found out that bringing the enemies stamina down [Red bar is their stamina] to be empty will cause their character to try and load their stunned animation, hitting them while they are doing said stunned animation will cause it to refill so they are no longer stunned...but what if I told you that you could abuse that and actually benefit from it as well?
(Using this trick is SUPER helpful, it makes the opponent unable to block and forced to keep taking damage no matter how hard they try to block)
The trick is simple really, your character should have a move to trip over your opponent causing them to..well...trip over or fall (HighFive has the easiest and best version of it and I definitely recommend him since he's kinda broken lol)...whatever you wanna call it, but you must hit them on the right frame because hitting them on the wrong frame will cause the bar to just refill, practicing the timing to hit them as early as possible from their get up animation is the key to succeeding.
(Edit: Using the Zappa lads is more preferable due to their combo attack being more broken and useful then the tripping attack that others have, even better than high five who I believed was already the most broken character in this game but oh damn do the zappas prove me wrong lol, to do their attack simply press forward then back then forward and use a punch attack and combo it into itself or other attacks to do said combo)
All characters have different get up animations and some can be slower or faster than others, understanding that will be what decides whether you win or lose the run.
The cpu tries to run away or block or spam certain things that can ruin the run so knowing and doing this (with some RNG luck as well) will help you getting a good time.
Goodluck future runners, whether someone chooses to run this for fun or get the WR I wish you the best of luck!