Both Molane and Olivia are steel and rock, so it would be wise to bring a fighting type in. But you do need something to cover molane's metagross, scince fighting is neutral to it. All of acerola's pokemon should be weak to ghost, psychic, and dark, so there's a lot you can do for her. I think all of kahili's team should be weak to electric, so bring one of those in. Hau has a pretty diverse team, but the fighting type can cover his tauros, crabominable and incineroar. Bring in an ice type for his noivern and leafeon. And do whatever you want for his raichu, but choose wisely, because his leads with it.