you don't need awakened units to clear it. As you saw in lafate's guide , it can be done with mostly silvers. But you do need higher levels tho



That being said , both sasha and uzume are very good units , but neither are priority ones. I suggest raising your HAT (healer/archer/tank) a bit more , and cc a second(even third in the future) healer and trying to aquire spica asap.



Other then that , you could raise claudia , and Imelia since both are pretty good units (especially imelia , looks like a very good duelist) , and awaken the usual : spica , berniece, uzume (very good passive) , katie , maybe a Iris , betty (if you want her for gold get) , etc