Might as well add to the pile.

The team here is Ling, Sylvie, Runda, Kaito, Esther, Skye
(some substitutions are likely possible)

Ling has the morgana rod in both forms, is passive provoke, and spends basically every turn shifting and then using the self-reraise skill from Phoenix, passively generating 3k morale per turn. On the turn we hit threshold (6 for me) and the kill turn (10 for me) she instead uses her beast killer buff.

Sylvie pretty much does all her usual sylvie things. Physical mit, Wind/Earth resist for runda, Poison cure, insect killer, 100% earth amp for the bursts, LB buffs. I had her set up as a secondary evade provoke with a counter orb, but when things go smoothly this never triggers.

Runda is the tank, set up with evade, physical bulk, and poppy's paintbrush a blizzard orb. He keeps up cover and his LB/SLB as much as possible, and handles the sealing with counters after turn 1. Important thing is to make sure good physical mitigation is maintained on him between his own LBs and Sylvie, since the boss reduces phys mit durations by an extra turn early in its own turn.

Kaito pretty much just spammed all his breaks (and imperils once above 150% morale) and chained EN with Esther. Contributed some damage, but much less than the next two. He also applied blinds with his 85% break skill that has a 50% chance per cast, but this could probably be done with a blind weapon instead at the cost of damage.

Esther and Skye were just the hardest hitters of the team, but weren't providing anything especially unique. They just spend all the odd turns recharging their LBs, and all the even turns using them. Skye had sealing weapons in the base form for safety, but I think Runda was able to handle all the turns on the successful run anyway.

Video of the clear, I messed up near the end and didn't want to re-record the whole thing, but it gets the idea of the team across and shows the proper 3b cap turn afterwards. I felt this clear was reasonably safe and not too specific/complicated in terms of tracking your own / the boss actions meticulously, as long as you're careful with that phys mit uptime. https://www.youtube.com/watch?v=Nf36gLKRWNI