Leaf Blade is learned by 28 species by level, 19 by machine and 2 by egg

Effect, in PokéAPI's words

“Has an increased chance for a critical hit.”

Who learns it

32 species in all, 8 of 18 games shown

Scarlet and Violet: 22 species

Species	Method	Level
Sceptile	Level up	Evolve
Shiftry	Level up	Evolve
Gallade	Level up	1
Snivy	Level up	28
Rowlet	Level up	30
Servine	Level up	32
Serperior	Level up	32
Leavanny	Level up	36
Grovyle	Level up	40
Dartrix	Level up	40
Fomantis	Level up	40
Victreebel	Level up	44
Decidueye	Level up	44
Lurantis	Level up	44
Skiddo	Level up	45
Iron Valiant	Level up	49
Iron Leaves	Level up	49
Leafeon	Level up	50
Gogoat	Level up	55
Nuzleaf	Level up	57
Virizion	Level up	63
Tropius	Egg

Legends Arceus: 7 species

Species	Method	Level
Leafeon	Level up	25
Turtwig	Level up	34
Grotle	Level up	34
Torterra	Level up	34
Rowlet	Level up	34
Dartrix	Level up	34
Gallade	Level up	43

Brilliant Diamond and Shining Pearl: 8 species

Species	Method	Level
Shiftry	Level up	1
Grovyle	Level up	40
Sceptile	Level up	42
Victreebel	Level up	44
Leafeon	Level up	50
Farfetch’d	Level up, Egg	55
Nuzleaf	Level up	57
Tropius	Egg

Sword and Shield: 19 species

Species	Method	Level
Shiftry	Level up, Machine	1
Rowlet	Level up, Machine	30
Grovyle	Level up, Machine	40
Dartrix	Level up, Machine	40
Fomantis	Level up, Machine	40
Sceptile	Level up, Machine	42
Decidueye	Level up, Machine	44
Lurantis	Level up, Machine	44
Leafeon	Level up, Machine	50
Farfetch’d	Level up, Machine	55
Kartana	Level up, Machine	55
Sirfetch’d	Level up, Machine	55
Nuzleaf	Level up, Machine	57
Virizion	Level up, Machine	63
Mew	Machine
Bellossom	Machine
Celebi	Machine
Gallade	Machine
Lilligant	Machine

Ultra Sun and Ultra Moon: 22 species

Species	Method	Level
Bellossom	Level up	1
Gallade	Level up	1
Virizion	Level up	1, 55
Grovyle	Level up	23
Sceptile	Level up	23
Fomantis	Level up	23
Lurantis	Level up	23
Nuzleaf	Level up	28
Snivy	Level up	28
Servine	Level up	32
Serperior	Level up	32
Leavanny	Level up	36
Rowlet	Level up	36
Dartrix	Level up	42
Kartana	Level up	43
Victreebel	Level up	44
Decidueye	Level up	44
Leafeon	Level up	45
Skiddo	Level up	45
Gogoat	Level up	55
Farfetch’d	Egg
Tropius	Egg

Sun and Moon: 22 species

Species	Method	Level
Bellossom	Level up	1
Gallade	Level up	1
Virizion	Level up	1, 55
Grovyle	Level up	23
Sceptile	Level up	23
Fomantis	Level up	23
Lurantis	Level up	23
Nuzleaf	Level up	28
Snivy	Level up	28
Servine	Level up	32
Serperior	Level up	32
Leavanny	Level up	36
Rowlet	Level up	36
Dartrix	Level up	42
Kartana	Level up	43
Victreebel	Level up	44
Decidueye	Level up	44
Leafeon	Level up	45
Skiddo	Level up	45
Gogoat	Level up	55
Farfetch’d	Egg
Tropius	Egg

Omega Ruby and Alpha Sapphire: 16 species

Species	Method	Level
Bellossom	Level up	1
Gallade	Level up	1
Virizion	Level up	1, 67
Grovyle	Level up	23
Sceptile	Level up	23
Nuzleaf	Level up	28
Snivy	Level up	28
Servine	Level up	32
Serperior	Level up	32
Leavanny	Level up	36
Leafeon	Level up	45
Skiddo	Level up	45
Victreebel	Level up	47
Gogoat	Level up	55
Farfetch’d	Egg
Tropius	Egg

X and Y: 15 species

Species	Method	Level
Bellossom	Level up	1
Gallade	Level up	1
Virizion	Level up	1, 67
Snivy	Level up	28
Grovyle	Level up	29
Sceptile	Level up	29
Servine	Level up	32
Serperior	Level up	32
Leavanny	Level up	36
Leafeon	Level up	45
Skiddo	Level up	45
Victreebel	Level up	47
Gogoat	Level up	55
Farfetch’d	Egg
Tropius	Egg

Changed over time

One change since Generation III

1. Through Gen IIIPower 7090 from Diamond and Pearl, Generation IV