The settings within the game allow you to change the time limit for episode matches down to the minimum of one minute. If there is no winner after one minute the game will kill both players allowing you to consistently beat each match in one minute IGT, ~1:15s RTA with PC loads. I have created a flexible route to best exploit this ability.

Whilst you technically still beat the game, this category has been separated because you have to change the default settings. 
Formally, you can complete each episode with a score less than "Perfect!" meaning matches can be lost and continued. Be aware that a "Perfect!" score must be achieved in episode three if you have not beaten the game prior to starting a run or else you will not be able to progress by unlocking episode four and onwards.

After many attempts I found that reducing the time limit of matches encourages the enemy player to spend less time idling making the fight more intense. The difficulty setting only affects how much damage the attack of an enemy player can deal along with how often they initiate a block stance. Neither parties health meters are affected by the difficulty setting.

Episode one:
WIN match #1
¤ I find this match inconsistent and if I can't beat Busta Rhymes in 30s or less then I'll usually death abuse.
LOSE matches #2, #3

Episode two:
WIN match #1
LOSE matches #2, #3

Episode three:
LOSE all matches

Episode four:
WIN match #2
¤ The "Cousin Grimm" character is very overpowered and can typically finish this match in around 20s.
LOSE matches #1, #3

Episode five:
LOSE all matches

Episode six:
Swap characters and WIN match #2
¤ The "Cousin Grimm" character is very overpowered and can typically finish this match in around 20s.
LOSE matches #1, #3

This route is not mandatory.

Best of luck!

Yes. If you are going to run this category on console I suggest you block the enemies moves as often as you can in order to reduce lag. Also, it's ideal that the match finishes through both parties being killed at the end of the time limit rather than through a special "KILL!" move (finale move) as these are generally slower and take longer to finish in comparison.

After some testing I found that the fighting styles for the Cindy Margolis and Busta Rhymes characters are considerably aggressive meaning fights against them could be optimised should a consistent way to die from their attacks early be found. You would do this by NOT holding a block stance and letting said enemy characters kill you, practically speaking in under 45s IGT as the pairs finale moves are not too long saving ~3s RTA in those respective rounds as opposed to both parties dying from the timer reaching zero. The catch is that this strat includes having to watch unskippable victory cutscenes which take longer making a possible timesave negligible. However, the idea IS viable in practice if you are able to be killed by enemy moves in under 30s IGT meaning an expected time save of ~12s RTA in those respective rounds.

Edit: The victory cutscene for Cindy Margolis turns out to be the longest in the game so don't bother with her, I'm keeping this post as a journal of progress. Please refer to the new route below!

So it turns out the above route (first post) is whack in practice and I figured out a much better one making sub 20 runs virtually free. It's good to see this game get more optimised.

Remember to set the game difficulty to the max.

I need to explain a few terms for this new route!
LOSE = Die from end of time limit, hold block stance.
KILLED = Die from an enemy characters finishing move, preferably within 30 seconds.
WIN = Win the match, preferably within 30 seconds.

Episode one: 
KILLED match #1
LOSE matches #2, #3

Episode two: 
LOSE all matches

Episode three: 
KILLED matches #1, #3
LOSE match #2

Episode four: 
KILLED match #1
WIN match #2
LOSE match #3

Episode five: 
KILLED matches #1, #3
LOSE match #2

Episode six: 
KILLED match #1
Swap characters and WIN match #2
LOSE match #3

The matches you are going to lose are routed considering how long the respective enemies victory cutscenes are and the enemies apparent lack of an aggressive AI especially in comparison to the Busta Rhymes character for example.

If anybody requires further clarification then let me know.