After passing through the Poni Wilds, you meet Hapu in Ancient Poni Path before heading east to Poni Breaker Coast.
Go to the right to start a cut scene. Machamp will be added to your Ride Pager.
Machamp can push large square boulders if you press B while he is carrying you, so if you wish, you can go to the places where large boulders blocked your path. You can also go to the back rooms of the ruins on Akala Island and Ula'ula Island, but there is nothing to find there right now.
Machamp Shove Spots
In the west side of Diglett's Tunnel on Akala Island, you can push a boulder with Machamp and go outside to the Lighthouse Point in Konikoni City. There is a hidden Big Pearl on the hill just above the slope there. To the left of that, you find TM61 Will-O-Wisp. There is a Totem Sticker on the lighthouse.
In the eastern area of Lush Jungle, there is a boulder that you can push with Machamp. Beyond that boulder, there is a cave. Go in and push the boulder three times east, then one time north into the hole. South of the boulder, you find a Hyper Potion. East of that, there is a hidden Rare Candy. To the north, leave the cave to find TM53 Energy Ball.
Back in Ancient Poni Path
Return to Ancient Poni Path. Go inside Hapu's house and approach the Mudsdale near the TV. If you found the photo in a book in the Malie City Library, there will be a cut scene, and you will get a Heart Scale.
You can talk to the Miltank in Hapu's house to heal up your pokémon.
You can check on the leftmost bed in the bedroom in Hapu's house to get an Awakening.
Go through one of the back doors of the house to reach the courtyard. There is a hidden Revival herb above the tree in the middle.
There is a Shiny Stone northeast of Hapu's house.
South of Hapu's house, go to the right of the wall, then go down and west through the grass to find an Adrenaline Orb.
Go southeast from Hapu's house. You can see a TM to the south, but you can't reach it yet.
To the right of the TM, there is a ramp down to Poni Breaker Coast, and if you go east from there, you can battle Collector Raymond. He has a level 44 Turtonator and a level 44 Drampa. You get 1408 Pokédollars for winning.
To the right of the Collector, there is a hidden PP Up.
To the right of that, there is a Totem Sticker.
Go south and go down the ramp to reach Poni Breaker Coast.
Poni Breaker Coast
To the left of where you entered the area, you can battle Sightseer Jamie. She has a level 44 non-Alolan Sandshrew and a level 44 non-Alolan Persian. You get 2640 Pokédollars for winning.
Go to the left and go up the ramp, then go to the right through the grass to get TM55 Scald.
Go west, then south, to return to Poni Breaker Coast, then go east until you see a geyser. From there, go south and get in the water, and keep going south to find a Max Revive underwater.
Go north and get back on dry land. Go east past the geyser. You can battle Swimmer Derek. He has a level 44 Dragalge. You get 1056 Pokédollars for winning.
Go south past the swimmer and go clockwise around the hole to find a hidden Calcium on a small rock.
From there, go east, then go up the path between the two stone statues to reach the Ruins of Hope.