First meaning the one you can ride. I'm assuming it's a no, which is probably why you can get a second. I'm still curious though.
However, since this creature acts as a bike as well as a fighting Pokémon, you're unable to trade it since it's necessary to have to get around. Fortunately, you can catch another Koraidon or Miraidon that can be traded for the other Legendary that isn't in your game.
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