>>44776642>>44776683>>44776695So in general all Pokemon have bonds/friendships with their trainers, Gardevoirs have that and also a protective spirit towards their trainer. Gardevoir do not have to like you, respect you, or care about your happiness, they just have to protect you. So if a breeder raised one and got one to evolve in a time frame in which the Gardevoir did not form any Bond/Friendship with the breeder, then it would probably be okay with being traded to a new person, but if they got attached or formed some kind of personal bond with the breeder, then no they would not want to leave making it much harder to trade them.
Pokemon trading to me is always kinda weird, the video games don't have pokemon have honest agency so they can't say no, but in the anime they would be able to. You don't remove a Pokemon's agency from the choice, so its always going to have some layer of the Pokemon accepting to leave willingly. You can't really force them to do anything they don't want to. So it'd be easier to just give them away as an Egg or fairly newly born Ralts.