Pokemon X&Y: Pokemon Cloning Glitch
Finally, we have confirmation that you can indeed clone Pokemon in Pokemon X&Y. The awesome YouTuber Mootypwns (seriously you need to subscribe to her) has confirmed that you can indeed clone Pokemon similarly like in past games.
In order to perform the glitch you will need two copies of Pokemon X&Y and as well two 3DS/2DS. You will need to set up a trade and disconnect at a certain point to duplicate the Pokemon. Mootypwns explains it well in the video.