Does Wonder Trade (or the same thing with a new name) return in Sun & Moon?
How far into the game must one be in order to unlock it?
To access Wonder Trade, just follow these instructions:
And so on.
Hope I helped. :)
Source: copied from http://www.idigitaltimes.com/pokemon-sun-and-moon-how-wonder-trade-and-what-watch-out-569425 since I don't know how to quote with the markdown anymore ugh