Here is the full list of all 34 EARTHLOCK achievements.
Filled the library with mementos
Unlocked all prison cells in Karba Prison
Crafted one of every weapon
Scavenged all scrap piles
Released all the Golden Bibis
Planted one of every critter plant
Levelled every type of plant to level 3
Crafted one of every Perk Talent
Defeated the Hollow Knight
Completed the game
Equipped a Talent in every available slot
Levelled all characters to level 20
Defeated one of every enemy
Arrived at the Memory Chamber
Received the Lys Aegis Talent from Lady Lumia
Released 50 tormented Ghosts
Cured Benjo and rescued Bran
Dug up all treasure zones
Got all the paintings for Plumpet Library
Released all the barnacles to play on Plumpet Beach
Gained Gold Rank in all Tournaments
Levelled up all Bonds to level 5
Grew a plant in every garden slot
Liberated the Great Wave
Assembled PAT
Olia rejoined the party
Harvested 10 000 fruits
Defeated the Mushriga
Opened 50 chests
Rescued Taika from the goblin
Helped Ive after she crashed the plane
Arrived at Plumpet Island
Gnart joined the party
Defeated the Temple Guardian