How do duplacate Pokemon on diamond and pearl?
Well, I could be wrong, but I think it is impossible. Me and my
sister tried and failed. We tried to trade two Bidoofs, a boy and a
girl, so we could tell...but it didn't work. I think it silently
saves after you make the trade, so there's really no turning back-
just trading back.
However, you CAN duplicate goods underground. First, get the
good you want to duplicate. Then, go back to the surface and
underground again. Make sure the friend who you want to give the
duplicate to is there. Then talk to them and say you want to give
them something. Give the good that you want to duplicate. Then turn
the power off once you say good-bye. You will still have the good,
and so will your friend!
But if you just want two of the same good, you'll have to have
the friend trade it back.