Sadly, can’t offer too much advice, aside from some general (and not always helpful) pvp ones, since I can no longer look back at the AI team to be more specific.
- You can try putting a healer in the front spot, since they are generally rather tanky for needing high HP for stronger heals.
- See if you can silence, sleep, defense break or otherwise debuff the enemies to take them out faster. Silence (and Provoke to a certain degree) locks out their 2nd and 3rd skill; sleep makes them unable to attack and guarantees a crit when attacking them; defense break basically doubles received damage, while reduced hitrate halves their damage.
- Alternatively, maybe try to focus down AoE opponents in the enemy team first to ensure your team survives longer?
- Since you mention shields. I don’t remember the enemy team, but usually Crozet has that passive ability. If he is actually on it and if you manage to take him out first, the others won’t be receiving his shields for the rest of the fight.
- Obviously, make sure your selected heroes are equipped, somewhat skilled up, awakened as much as possible and so on.
- Again, this is obvious, but keep element affinity in mind when selecting a team. Like, Baiken is earth-aspected and extra vulnerable to Elphelt (fire). But if you need her to take out some water-aspected opponent in the team, that’s a calculated risk.
Didn’t have any problems with this fight myself. If memory serves, the team I used was lvl 60 Luna, Roana, Tenebria and lvl 50 Yufine. This has a combination of aoe silences, sleeps, defense breaks and slows, while also having strong single target damage and barriers/heals/revives.
Edit: Ah, and on what to prioritize between gearing and promotion to 6 stars. I would suggest trying to gear up your core/most used characters first, while slowly working on gathering the phantasmals for promotion. With some dedication and steady play, one can save up enough phantasmals to promote 1 character to 60 every month with natural weekly progression.
See it this way: promoting characters to 60 mostly improves their stats, but gear and set bonuses are what makes everyday life easier. Once you have a geared team that can steadily take out lvl 50+ opponents in story mode and events, then promotion to 60 will make your life easier.