Crabhammer is learned by 9 species by level and 2 by egg

Effect, in PokéAPI's words

“Has an increased chance for a critical hit.”

Who learns it

10 species in all, 8 of 24 games shown

Scarlet and Violet: 8 species

Species	Method	Level
Crabrawler	Level up	37
Corphish	Level up	44
Gligar	Level up	45
Gliscor	Level up	45
Crawdaunt	Level up	52
Clauncher	Level up	55
Clawitzer	Level up	63
Klawf	Egg

Brilliant Diamond and Shining Pearl: 4 species

Species	Method	Level
Krabby	Level up	44
Corphish	Level up	44
Crawdaunt	Level up	52
Kingler	Level up	54

Sword and Shield: 6 species

Species	Method	Level
Krabby	Level up	44
Corphish	Level up	44
Crawdaunt	Level up	52
Kingler	Level up	54
Clauncher	Level up	55
Clawitzer	Level up	63

Let's Go Pikachu and Let's Go Eevee: 2 species

Species	Method	Level
Krabby	Level up	36
Kingler	Level up	41

Ultra Sun and Ultra Moon: 7 species

Species	Method	Level
Clauncher	Level up, Egg	30
Clawitzer	Level up	30
Crabrawler	Level up	37
Krabby	Level up	41
Corphish	Level up	43
Crawdaunt	Level up	48
Kingler	Level up	56

Sun and Moon: 7 species

Species	Method	Level
Clauncher	Level up, Egg	30
Clawitzer	Level up	30
Crabrawler	Level up	37
Krabby	Level up	41
Corphish	Level up	43
Crawdaunt	Level up	48
Kingler	Level up	56

Omega Ruby and Alpha Sapphire: 6 species

Species	Method	Level
Clauncher	Level up, Egg	30
Clawitzer	Level up	30
Krabby	Level up	41
Corphish	Level up	43
Crawdaunt	Level up	48
Kingler	Level up	56

X and Y: 6 species

Species	Method	Level
Clauncher	Level up, Egg	30
Clawitzer	Level up	30
Corphish	Level up	38
Krabby	Level up	41
Crawdaunt	Level up	44
Kingler	Level up	56

Changed over time

2 changes since Generation I

1. Through Gen IVAccuracy 85%90% from Black and White, Generation V
2. Through Gen VPower 90100 from X and Y, Generation VI