If you chose Fennekin, it will be Zapdos. After encountering one of the birds, check its entry in your Coastal Kalos Pokedex.

they come across a Pokémon they’ve never seen before - one that Ash’s Pokédex can’t identify! Its Trainer introduces herself as Alexa, a Pokémon journalist from the faraway Kalos region.

Kalos is the setting for the upcoming Pokemon ... Therefore, it seems its Mega Evolution design has already been teased.

I collected every Pokemon, completed the Pokedex for the first time ... more than most because of my time with it. The region of Kalos is beautifully messy. The experiment with 3D was rough ...