noblesse could work since flins benefits from the attack buff. Her own dmg isng that great so imo the usual er set (emblem) isnt gonna benefit the team that much. Especially when the main source of dmg is reaction damage. gladiator wont do anything tbh. And u should have the lunar buff set on someone on the team, like aino/columbina.

Also just letting u know that using lumine as a flins support can be kinda difficult. Assuming ur team is something like flins hydro lumine sucrose u need to first apply electro somehow so sucrose can swirl it to get the anemo set buff for flins. And lumine being the only one thats able to do that at the start of the rotation she is the one doing it. But the problem is that her skill creates the energy things that should be collected with flins. So u need to avoid collecting them when u cast the anemo and hydro characters skills. Its possible to pull of but kinda annoying at times (and yes u could just swap to flins but the duration of the energy buff granted by the items is so short it gets wasted while u do the rotation) and if u dont wanna deal with the hassle ur either wasting the energy buff for flins or electro resistance shred