I have Pixelmon 3.3.9 , Trainer Commands, PixelExtras and Wondertrade. Im not sure if the command originates from Pixelmon or just other sidemods.
Also! I remember a command that came from PixelExtras or Trainer Commands, it basically let me edit the moves my PokeMon have, even if they cant learn it. Its not the /setparty command.