The main danger of this fight in a normal play is Meiling sniping Marisa and/or Patchouli with Brilliant Light Gem, then proceed to stall you out of resources with her ~6000 HP (accounting for that heal) and high resistances across the board. Since she can't do that in NG+, she won't be winning the battle as long as you're trying somewhat seriously.
Very easy. ~6000 HP with her one-time heal accounted plus resistance to many elements lets her stick around for a while, but It's not like she can actually kill off my tanks with her whooping 80 ATK anyways.
![](https://i.ytimg.com/vi/Ho1mQGHWeJw/mqdefault.jpg)