For reference, I tackled this stage with my usual Hraesvelgr clearing team.
Squad 1 is a s-counter team with Hydrangea, Habranthus, Pink (Miko), Anemone (base) and Fritillaria, memoried up for defense + overheal.
This squad rushed through the pests up until the last boss, leaving only 5-10% of their HP bars, which the next squad easily mopped up.