Electro Ball is learned by 24 species by level, 76 by machine and 1 by egg

Effect, in PokéAPI's words

“Power is higher when the user has greater Speed than the target, up to a maximum of 150.”

Who learns it

76 species in all, 8 of 9 games shown

Scarlet and Violet: 61 species

Species	Method	Level
Kilowattrel	Level up, Machine	Evolve
Raichu	Level up, Machine	1
Lanturn	Level up, Machine	1
Chinchou	Level up, Machine	4
Pikachu	Level up, Machine	12
Magnemite	Level up, Machine	12
Magneton	Level up, Machine	12
Magnezone	Level up, Machine	12
Plusle	Level up, Machine	19
Minun	Level up, Machine	19
Rotom	Level up, Machine	20
Joltik	Level up, Machine	20
Galvantula	Level up, Machine	20
Voltorb	Level up, Machine	22
Electrode	Level up, Machine	22
Mareep	Level up, Machine	22
Flaaffy	Level up, Machine	25
Ampharos	Level up, Machine	25
Pachirisu	Level up, Machine	25
Electabuzz	Machine
Jolteon	Machine
Zapdos	Machine
Mewtwo	Machine
Mew	Machine
Pichu	Machine
Elekid	Machine
Raikou	Machine
Shinx	Machine
Luxio	Machine
Luxray	Machine
Electivire	Machine
Blitzle	Machine
Zebstrika	Machine
Eelektrik	Machine
Eelektross	Machine
Thundurus	Machine
Zekrom	Machine
Dedenne	Machine
Charjabug	Machine
Vikavolt	Machine
Magearna	Machine
Scorbunny	Machine
Raboot	Machine
Cinderace	Machine
Toxtricity	Machine
Pincurchin	Machine
Morpeko	Machine
Regieleki	Machine
Pawmi	Machine
Pawmo	Machine
Pawmot	Machine
Tadbulb	Machine
Bellibolt	Machine
Wattrel	Machine
Rabsca	Machine
Sandy Shocks	Machine
Iron Treads	Machine
Iron Thorns	Machine
Gholdengo	Machine
Miraidon	Machine
Raging Bolt	Machine

Brilliant Diamond and Shining Pearl: 17 species

Species	Method	Level
Raichu	Level up	1
Lanturn	Level up	1
Chinchou	Level up	4
Pikachu	Level up	12
Magnemite	Level up	12
Magneton	Level up	12
Magnezone	Level up	12
Plusle	Level up	19
Minun	Level up	19
Rotom	Level up	20
Voltorb	Level up	22
Electrode	Level up	22
Mareep	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Electrike	Egg

Sword and Shield: 46 species

Species	Method	Level
Raichu	Level up, Machine	1
Lanturn	Level up, Machine	1
Chinchou	Level up, Machine	4
Pikachu	Level up, Machine	12
Magnemite	Level up, Machine	12
Magneton	Level up, Machine	12
Magnezone	Level up, Machine	12
Rotom	Level up, Machine	20
Joltik	Level up, Machine	20
Galvantula	Level up, Machine	20
Electabuzz	Machine
Jolteon	Machine
Mewtwo	Machine
Mew	Machine
Elekid	Machine
Electrike	Machine
Manectric	Machine
Shinx	Machine
Luxio	Machine
Luxray	Machine
Electivire	Machine
Emolga	Machine
Thundurus	Machine
Zekrom	Machine
Helioptile	Machine
Heliolisk	Machine
Dedenne	Machine
Charjabug	Machine
Vikavolt	Machine
Togedemaru	Machine
Tapu Koko	Machine
Xurkitree	Machine
Magearna	Machine
Zeraora	Machine
Scorbunny	Machine
Raboot	Machine
Cinderace	Machine
Wooloo	Machine
Dubwool	Machine
Yamper	Machine
Boltund	Machine
Toxtricity	Machine
Morpeko	Machine
Dracozolt	Machine
Arctozolt	Machine
Regieleki	Machine

Ultra Sun and Ultra Moon: 23 species

Species	Method	Level
Lanturn	Level up	1, 9
Chinchou	Level up	9
Pikachu	Level up	13
Plusle	Level up	19
Minun	Level up	19
Voltorb	Level up	22
Electrode	Level up	22
Electabuzz	Level up	22
Mareep	Level up	22
Elekid	Level up	22
Electivire	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Emolga	Level up	26
Magnemite	Level up	29
Magneton	Level up	29
Magnezone	Level up	29
Joltik	Level up	29
Galvantula	Level up	29
Rotom	Level up	43
Tapu Koko	Level up	58
Electrike	Egg

Sun and Moon: 23 species

Species	Method	Level
Lanturn	Level up	1, 9
Chinchou	Level up	9
Pikachu	Level up	13
Plusle	Level up	19
Minun	Level up	19
Voltorb	Level up	22
Electrode	Level up	22
Electabuzz	Level up	22
Mareep	Level up	22
Elekid	Level up	22
Electivire	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Emolga	Level up	26
Magnemite	Level up	29
Magneton	Level up	29
Magnezone	Level up	29
Joltik	Level up	29
Galvantula	Level up	29
Rotom	Level up	43
Tapu Koko	Level up	58
Electrike	Egg

Omega Ruby and Alpha Sapphire: 22 species

Species	Method	Level
Lanturn	Level up	1, 9
Chinchou	Level up	9
Pikachu	Level up	13
Plusle	Level up	19
Minun	Level up	19
Voltorb	Level up	22
Electrode	Level up	22
Electabuzz	Level up	22
Mareep	Level up	22
Elekid	Level up	22
Electivire	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Emolga	Level up	26
Magnemite	Level up	29
Magneton	Level up	29
Magnezone	Level up	29
Joltik	Level up	29
Galvantula	Level up	29
Rotom	Level up	43
Electrike	Egg

X and Y: 22 species

Species	Method	Level
Pikachu	Level up	18
Electabuzz	Level up	22
Mareep	Level up	22
Elekid	Level up	22
Electivire	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Emolga	Level up	26
Chinchou	Level up	28
Voltorb	Level up	29
Electrode	Level up	29
Plusle	Level up	29
Minun	Level up	29
Joltik	Level up	29
Galvantula	Level up	29
Lanturn	Level up	30
Magnemite	Level up	32
Magneton	Level up	34
Magnezone	Level up	34
Rotom	Level up	43
Electrike	Egg

Black 2 and White 2: 22 species

Species	Method	Level
Pikachu	Level up	18
Electabuzz	Level up	22
Mareep	Level up	22
Elekid	Level up	22
Electivire	Level up	22
Flaaffy	Level up	25
Ampharos	Level up	25
Pachirisu	Level up	25
Emolga	Level up	26
Chinchou	Level up	28
Voltorb	Level up	29
Electrode	Level up	29
Plusle	Level up	29
Minun	Level up	29
Joltik	Level up	29
Galvantula	Level up	29
Lanturn	Level up	30
Magnemite	Level up	32
Magneton	Level up	34
Magnezone	Level up	34
Rotom	Level up	43
Electrike	Egg