Close Combat is learned by 53 species by level, 123 by machine and 7 by egg

Effect, in PokéAPI's words

“Lowers the user’s Defense and Special Defense by one stage after inflicting damage.”

Who learns it

125 species in all, 8 of 13 games shown

Scarlet and Violet: 95 species

Species	Method	Level
Infernape	Level up, Machine	Evolve
Staraptor	Level up, Machine	Evolve
Mankey	Level up, Machine	33
Hitmonlee	Level up, Machine	36
Hitmonchan	Level up, Machine	36
Hitmontop	Level up, Machine	36
Monferno	Level up, Machine	36
Primeape	Level up, Machine	39
Annihilape	Level up	39
Makuhita	Level up, Machine	40
Pawmot	Level up, Machine	44
Hariyama	Level up, Machine	46
Kubfu	Level up, Machine	48
Urshifu	Level up, Machine	48
Crabrawler	Level up, Machine	49
Crabominable	Level up, Machine	49
Zangoose	Level up, Machine	50
Passimian	Level up, Machine	50
Falinks	Level up, Machine	50
Hakamo-o	Level up, Machine	56
Quaquaval	Level up, Machine	58
Heracross	Level up, Machine	60
Lucario	Level up, Machine	60
Kommo-o	Level up, Machine	60
Sneasler	Level up, Machine	60
Gallade	Level up, Machine	63
Great Tusk	Level up, Machine	63
Iron Hands	Level up, Machine	63
Iron Valiant	Level up, Machine	63
Iron Leaves	Level up, Machine	63
Cobalion	Level up, Machine	70
Terrakion	Level up, Machine	70
Virizion	Level up, Machine	70
Keldeo	Level up, Machine	70
Zacian	Level up, Machine	77
Zamazenta	Level up, Machine	77
Meloetta	Level up, Machine	78
Koraidon	Level up, Machine	84
Growlithe	Machine
Arcanine	Machine
Poliwrath	Machine
Scyther	Machine
Tauros	Machine
Mew	Machine
Snubbull	Machine
Granbull	Machine
Scizor	Machine
Teddiursa	Machine, Egg
Ursaring	Machine
Combusken	Machine
Blaziken	Machine
Breloom	Machine
Meditite	Machine
Medicham	Machine
Crawdaunt	Machine
Riolu	Machine
Toxicroak	Machine
Pignite	Machine
Emboar	Machine
Timburr	Machine
Gurdurr	Machine
Conkeldurr	Machine
Krookodile	Machine
Scraggy	Machine
Scrafty	Machine
Eelektross	Machine
Haxorus	Machine
Beartic	Machine
Mienfoo	Machine
Mienshao	Machine
Golurk	Machine
Rufflet	Machine
Braviary	Machine
Chesnaught	Machine
Hawlucha	Machine
Decidueye	Machine
Incineroar	Machine
Lycanroc	Machine
Mudbray	Machine
Mudsdale	Machine
Solgaleo	Machine
Arrokuda	Machine
Barraskewda	Machine
Perrserker	Machine
Zarude	Machine
Glastrier	Machine
Kleavor	Machine
Ursaluna	Machine
Ceruledge	Machine
Palafin	Machine
Flamigo	Machine
Brute Bonnet	Machine
Slither Wing	Machine
Okidogi	Machine
Iron Boulder	Machine

Legends Arceus: 16 species

Species	Method	Level
Staraptor	Level up	Evolve
Lopunny	Level up	40
Machop	Level up	43
Machoke	Level up	43
Machamp	Level up	43
Scyther	Level up	43
Scizor	Level up	43
Kleavor	Level up	43
Sneasler	Level up	43
Heracross	Level up	47
Riolu	Level up	47
Lucario	Level up	47
Croagunk	Level up	47
Toxicroak	Level up	47
Gallade	Level up	52
Infernape	Level up	57

Brilliant Diamond and Shining Pearl: 20 species

Species	Method	Level
Infernape	Level up	Evolve, 1
Staraptor	Level up	Evolve, 1
Blaziken	Level up	1
Mankey	Level up, Egg	36
Hitmonlee	Level up	36
Hitmonchan	Level up	36
Hitmontop	Level up	36
Monferno	Level up	36
Primeape	Level up	39
Makuhita	Level up	40
Hariyama	Level up	46
Zangoose	Level up	50
Heracross	Level up	60
Lucario	Level up	60
Gallade	Level up	63
Growlithe	Egg
Machop	Egg
Pinsir	Egg
Snubbull	Egg
Teddiursa	Egg

Sword and Shield: 75 species

Species	Method	Level
Hitmonlee	Level up, Machine	36
Hitmonchan	Level up, Machine	36
Hitmontop	Level up, Machine	36
Kubfu	Level up, Machine	48
Urshifu	Level up, Machine	48
Passimian	Level up, Machine	50
Falinks	Level up, Machine	50
Sawk	Level up, Machine	55
Hakamo-o	Level up, Machine	56
Heracross	Level up, Machine	60
Lucario	Level up, Machine	60
Kommo-o	Level up, Machine	60
Gallade	Level up, Machine	63
Cobalion	Level up, Machine	70
Terrakion	Level up, Machine	70
Virizion	Level up, Machine	70
Keldeo	Level up, Machine	70
Xerneas	Level up, Machine	75
Zacian	Level up, Machine	77
Zamazenta	Level up, Machine	77
Zeraora	Level up, Machine	96
Marshadow	Level up, Machine	99
Growlithe	Machine
Arcanine	Machine
Poliwrath	Machine
Machop	Machine
Machoke	Machine
Machamp	Machine
Farfetch’d	Machine
Pinsir	Machine
Tauros	Machine
Mew	Machine
Blaziken	Machine
Sharpedo	Machine
Crawdaunt	Machine
Absol	Machine
Lopunny	Machine
Gurdurr	Machine
Conkeldurr	Machine
Krookodile	Machine
Scrafty	Machine
Escavalier	Machine
Haxorus	Machine
Mienfoo	Machine
Mienshao	Machine
Golurk	Machine
Bouffalant	Machine
Rufflet	Machine
Braviary	Machine
Pangoro	Machine
Honedge	Machine
Doublade	Machine
Aegislash	Machine
Tyrunt	Machine
Tyrantrum	Machine
Hawlucha	Machine
Incineroar	Machine
Lycanroc	Machine
Mudbray	Machine
Mudsdale	Machine
Bewear	Machine
Golisopod	Machine
Tapu Bulu	Machine
Solgaleo	Machine
Buzzwole	Machine
Pheromosa	Machine
Arrokuda	Machine
Barraskewda	Machine
Clobbopus	Machine
Grapploct	Machine
Obstagoon	Machine
Perrserker	Machine
Sirfetch’d	Machine
Zarude	Machine
Glastrier	Machine

Ultra Sun and Ultra Moon: 34 species

Species	Method	Level
Infernape	Level up	Evolve, 1
Staraptor	Level up	Evolve, 1
Hitmonlee	Level up	1, 57
Hitmonchan	Level up	1, 66
Hitmontop	Level up	1, 55
Gallade	Level up	1, 53
Cobalion	Level up	1, 61
Terrakion	Level up	1, 61
Virizion	Level up	1, 61
Mankey	Level up, Egg	36
Monferno	Level up	36
Primeape	Level up	39
Makuhita	Level up	40
Sawk	Level up	41
Heracross	Level up	43
Passimian	Level up	43
Hariyama	Level up	46
Zeraora	Level up	47
Crabrawler	Level up	49
Crabominable	Level up	49
Zangoose	Level up	50
Marshadow	Level up	50
Lucario	Level up	55
Hakamo-o	Level up	63
Keldeo	Level up	73
Kommo-o	Level up	75
Meloetta	Level up	78
Xerneas	Level up	80
Growlithe	Egg
Machop	Egg
Pinsir	Egg
Snubbull	Egg
Teddiursa	Egg
Mudbray	Egg

Sun and Moon: 31 species

Species	Method	Level
Infernape	Level up	Evolve, 1
Staraptor	Level up	Evolve, 1
Hitmonlee	Level up	1, 57
Hitmonchan	Level up	1, 66
Hitmontop	Level up	1, 55
Gallade	Level up	1, 53
Cobalion	Level up	1, 61
Terrakion	Level up	1, 61
Virizion	Level up	1, 61
Mankey	Level up, Egg	36
Monferno	Level up	36
Primeape	Level up	39
Makuhita	Level up	40
Sawk	Level up	41
Heracross	Level up	43
Passimian	Level up	43
Hariyama	Level up	46
Crabrawler	Level up	49
Crabominable	Level up	49
Zangoose	Level up	50
Marshadow	Level up	50
Lucario	Level up	55
Keldeo	Level up	73
Meloetta	Level up	78
Xerneas	Level up	80
Growlithe	Egg
Machop	Egg
Pinsir	Egg
Snubbull	Egg
Teddiursa	Egg
Mudbray	Egg

Omega Ruby and Alpha Sapphire: 26 species

Species	Method	Level
Hitmonlee	Level up	1, 57
Hitmonchan	Level up	1, 66
Hitmontop	Level up	1, 55
Lucario	Level up	1, 55
Gallade	Level up	1, 53
Cobalion	Level up	1, 73
Terrakion	Level up	1, 73
Virizion	Level up	1, 73
Staraptor	Level up	34
Monferno	Level up	36
Infernape	Level up	36
Makuhita	Level up	40
Heracross	Level up	43
Hariyama	Level up	46
Sawk	Level up	48
Mankey	Level up, Egg	49
Zangoose	Level up	50
Primeape	Level up	59
Keldeo	Level up	73
Meloetta	Level up	78
Xerneas	Level up	80
Growlithe	Egg
Machop	Egg
Pinsir	Egg
Snubbull	Egg
Teddiursa	Egg

X and Y: 26 species

Species	Method	Level
Hitmonlee	Level up	1, 57
Hitmonchan	Level up	1, 66
Hitmontop	Level up	1, 55
Lucario	Level up	1, 55
Gallade	Level up	1, 59
Cobalion	Level up	1, 73
Terrakion	Level up	1, 73
Virizion	Level up	1, 73
Heracross	Level up	34
Staraptor	Level up	34
Monferno	Level up	36
Infernape	Level up	36
Makuhita	Level up	40
Zangoose	Level up	47
Sawk	Level up	48
Mankey	Level up, Egg	49
Hariyama	Level up	52
Primeape	Level up	59
Keldeo	Level up	73
Meloetta	Level up	78
Xerneas	Level up	80
Growlithe	Egg
Machop	Egg
Pinsir	Egg
Snubbull	Egg
Teddiursa	Egg