I heard of gts negotiations,and it can trade pokemon that you don't have in the pokedex,is it in diamond?
GTS Negotiations is a live trade. It looks for somebody just like in random matchup. When someon e is found you both choose 3 pokes. Then you do a live trade!The Global Trade Center is at the top of every Pokemon Center. It is the person on the right and you can trade pokemon with other people.{for bw}