About the battle itself.

1st step butterflies are the most dangerous thing here. You want to see them dead as fast as possible. All of them attack twice and get Crit buff and can kill a team of rainbow in one turn. That's why I put Evade girls + Revive in the first team.

2nd step is a bit easier. The main threat here is the Piece weak Scorpion. It's the only one with Crit buff. If I remember correctly, it attack only one girl and kill her with one attack. Here is kill in one turn or... kill in one turn. Once this one is dead, it's slightly easier. That's why team 3 has so many Crit with RRose and Accacia. RRose should be able to kill one of them in two hit (or one turn if she attack twice).

3rd step. Someone said CritPunk is less dangerous once the Ant and the Slug are dead. I didn't notice it but actually, the fight is easier when thoses little ones are dead. Even if the boss is still deadly, you will not see Kerria or Pinkladies hit land on the small pests.
In the best case, team 3 will survive the Scorpion and will be able to deal little damages on the last boss and maybe kill the small pests. In my succesful run, RRose killed the slug and it saved me. On the first turn, Kerria and Pinkladies killed the Ant and I fought only the Punkbee.
About the Punkbee itself, Crit attacks (and aove all, Crit skills) are the more dangerous things. It's regular attack with no Crit deals not that much damages on Kerria or Pinkladies. Saffron will die or Guts with only one Crit.

If you fight Scorpions with your 4th team, it's almost dead for you. if you fight Butterflies with your 4th team, just give up that run.

Then, good luck again. Try and try and try and pray to activate the secret power of Friendship and Love. You may be able to win with that