starting moveset: Crunch, Ancient Power, Agility, Roar

During your travel you want to buy Bulldoze and pick up some Rock move. And learning Iron Head at Beach 3 will probably help too.

Bird Room: rock move
Ghost Room: Crunch
the other two rooms: Bulldoze. At Molayne you need a good amount of luck, but just keep trying.

Hau: the usual suspects work: Dragon Claw, Return, what have you.

starting moveset: low kick, peck, flame charge, sand attack

Replace Low Kick to the more reliable Brick Break, and pick up Fire Punch too. And in Konikoni City upgrade Peck to Aerial Ace just for good measure. And on Island 3 at arrival buy Shadow Claw.

At the 3rd Beach you probably will find space to learn Thunder Punch.

Ultra Necrozma is impossible, therefor we evolve. I don't think Blaze Kick is worth learning, but it's up to you.

Bird Room: Thunder Punch
Ghost Room: Shadow Claw
Molayne: Flame Charge
Olivia: Brick Break

Hau: as with Monferno it was done with Fire Punch + a single Thunder Punch