It's works great getting rid of Belly Drummers, Swords Dancers, Power-Up Punchers, Stockpilers, Cotton Guarders, Terrakion-being-Beat-Up-by-Weavile-ers, Dragon Dancers, Speed Boosters, you name it.
To put it into one sentence, basically anything that's used for stat boosts is weak to this.
However, I wouldn't recommend it with Swagger, as the 2x Attack does indeed make your opponent do extra damage to itself. For that reason, Swagger has been banned to Übers on Showdown, from what I've heard. Yes, 2x Attack does make your own Pokémon vulnerable, but inverting it kinda' defeats the purpose of Swagger.