Pinkie Pie

Pinkie Pie, full name Pinkamena Diane Pie, is a female Earth pony and the leader of the Ponyville Gym.

Personality
Pinkie Pie is an energetic, excited, happy, bouncy, bubbly... basically just every synonym for energetic ever.

Pokemon Preference
Pinkie Pie likes happy looking Pokemon - such as Sylveon, Clefairy and Swirlix - alongside pink and cute Pokemon.

Fluttershy
Fluttershy and Pinkie Pie are good friends. The two of them don't like competing, and, despite their opposite personalities, get along

Rainbow Dash
Pinkie Pie and Rainbow Dash both share a love of pranks, and get along very well.

Maud Pie
Pinkie is energetic. Maud is boring.

But Pinkie Pie can tell what Maud is feeling, and is "best sister friends forever" with her.