I don't use Pokécheck, but I'm able to clone by copying save files. If you Pokétransfer with two DSes (I've read some people use a program on the computer or Pokécheck or something, which I don't like), I'll send over two Chanseys with the nickname Megumi and a Chansey without a nickname in 4th gen, and I'll grab one of the nicknamed Chanseys in 5th gen.
Otherwise, I'll just send only one nicknamed Chansey along with the non-nicknamed one.