Here's an easy way for you:
- Breed a Male Espurr that knows Fake Out with a Female Sneasel/Weavile.
- Once bred, hatch the egg, and the new Sneasel should know Fake Out.
Espurr learns Fake Out at Level 19.
You can also substitute Espurr with the following Pokemon if they are male and know Fake Out:
Meowth, Persian, Nuzleaf, Shiftry, Skitty, Delcatty, Glameow, Purugly, Purrloin, Liepard, Mienfoo, Mienshao, Meowstic (M or F), Pikachu, Raichu, Seel, Dewgong, Aipom, Delibird, Spinda, Kecleon, Chimchar, Monferno, Infernape, Ambipom, Buneary, Lopunny, Scraggy, Scrafty, Smeargle