You want a Ralts, you got one. Catch the first female Ralts that reveals the Trace Ability and name her Selena. She must solo Brawly to earn the right to evolve into Kirlia, and must evolve into Gardevoir after all of Harbinger's solos (Maxie and Sootopolis Gym) are complete. She must solo Wally's Gardevoir as a Gardevoir. GL!