On a serious note, Hawlucha is the hole in this guy's theory but someone pointed out that it could be argued that not a lot of pokemon have flying as their promary typing, so it might be an exception to the rule.

Reuniclus could be the Psychic Mega as it matches with Khu's riddle

Eelektross seems like a strong candidate for the Electric Mega because of Chandelure to reference Emmet and Ingo, but that's patternfag territory.