i hear awakend mercedes is good.
theorycrafting wall of text inc...
if i understood correctly the theory for party members you want:
1) storm bear --> slow atk debuf
2) healer healer --> nominally awakened shabelle (all res), awakened merc (powerhouse healing)
3) kymael --> combo with awakened shabelle for cycle ress
4) mc whatever, possibly mag priest with stamina gem (survivability)
if you want, you can put ravengale instead of one of the healer (shabelle) but if you do, shabelle must be mandatorily used as a callable ally..
then the most important aspect weapon effect:
1) bear --> cdr/cdr, he has to keep up the debuff as much as possible
2) both priests cdr//def reduction
3) kymael with cdr/def reduction or cdr/cdr, based on your own survivability status..
This is because in the long run, the stacking debuff from sharied will be TOO much, but you'll be fine due to the chain of kymael//shabelle putting you back in the loop.. You might even go with kymael helper, and let her die to be again in the game, but if you do it like this, you will be able to do the chain of "all dead--> mass ress" just once or twice, as when kymael dies, I doubt she gets ressed by shabelle aoe revive..
With bear slowing shariet attack you slow down the rate of accumulation for the debuff on your own team, and this is good as the debuff cannot be cleansed either.. you remove it by dieing and getting ressed..
blackaria here is terrible, as she prevented additional damage, but when she dies, if kymael was to die due to the debuff shortly after, she would NOT get ressed as she would still be in "ghost form" so to speak...
Alternative setup from a friend who's also on reddit
Priest - 1 CDR, 1 DefRed
Falcon - 1 CDR, 1 DefRed
Revengale - 1 CDR, 1 DefRed
Fryd - 1 ATKSPD Red, 1 DefRed
Blackaria - 1 CDR, 1 DefRed
Support Belle - 1 CDR, 1 DefRed
Formation - Swift Counterattack
Personally I think mine works a bit better on paper (I'm lacking the sss to fully finish that shariet party)..
Reason for this:
Shariet has insane defense, and as a metter of fact your own damage is negligible: you serve as a mean to buff nps and make sure they stay alive as long as possible..
this is achieved via strong heals (2 healers), direct buff via your units, indirect buff to your unit (def reduction as weapon effect) and direct debuff (bear atk speed reduction)..
If you want you can substitute in my formation bear with falcon, so you go for a more defense oriented party, but that's about it..
If only i had enough sss to sustain my theorycrafting...
But such is life..