There's a girl in the Motostoke Pokémon Center who will trade you a Skwovet for a Bunnelby.
There's a boy in the Turffield Stadium who will trade you a Kantonian Meowth for a Galarian one.
There's a woman in Hulbury Market who will trade you a Cottonee for a Minccino.
There's a girl near the small battlefield outside the Vault in Hammerlocke who will trade you a Togepi for a Toxel.
There's a man on top of one of the roofs in Stow-On-Side who will trade you either a Hatenna in Sword or an Impidimp in Shield for a Maractus (in both games).
There's a Pokekid (dressed as Eevee) in the Ballonea Stadium who will trade you a Unovan Yamask for a Galarian one.
There's an ice cream salesman around a fountain (not the baths) in Circhester who will trade you either a Throh in Sword or a Sawk in Shield for a Vanillish (in both games).
There's a Team Yell grunt near the Gym ring in Spikemuth who will trade you a Kantonian Mr. Mime for an Obstagoon.
There's an artist in one of the houses in Wyndon who will trade you a Duraludon for a Frosmoth.
Source
