I was watching
https://www.youtube.com/watch?v=KNPUQtWl3rQand some of what he says is really long winded and bullshit-y, but I think he might really be onto something with the Light and Sound type argument he brings up from 7:08 to about 10:00, and then later when he mentions that Yveltal appears to be blind.
To summarize:
*Xerneas has the light spectrum on its antlers and is in the middle of a huge lens flare when it is introduced
*Yveltal has eyes that look somewhat blind and is the only Pokemon in the trailer to make a sound
What he didn't bring up is that Sylveon has exactly the same eyes, but that could be considered support for his theory. It also has really big ears, and the little shape on the bottom of the egg that people are saying is a fairy wing could also be its ear; it's the same shape.
Light and Sound types, guys?
