I asked a question (link below) and they told me to talk to a lady (hex) outside some houses near the Poke Ball Factory. When I did she didn't give me anything but said this instead "Some Pokémon evolve when sent to someone by Link Trade. That's right. Haunter is one of those Pokémon. I'm all on my own, so I don't have anyone to Link Trade with. I'll use the GTS or Wonder Trade." I already beat the game, got the mega ring update, and have all the other Mega Stones found in Pokémon X. I didn't hack my game. Please help me! Thanks! :)
Probably because you are talking to the wrong person. There are several Hex Maniacs in Laverre Town, so you have to talk to the right one. Either that or you already got it without noticing, but I don't think she says that after you get the Mega Stone.