This is based on a character in a tv show called Dark Matter, a really great sci-fi show that just got cancelled
Trainer name: Five (new name) or Emily (original name)
Trainer type: Mechanical girl
Favorite type, types or theme for a team: steel or electrick to represent her talent and maybe other pokemon that are smart.
Ace Pokemon: Magearna really fits her but that is a legendary. so based on pokedex entry, it's either Mawile or Empoleon.
Character traits or personality: In the show she is the IT girl who is proficient in electrical engineering and quick with her wits. Not kidding, she is the youngest and potentially the most dangerous member on the team. One of the reason is because people were easily fooled by her age and innocent appearance. She is also caring person, willing to protect friends and even strangers if she found them worth her saving. She also does not gives up easily, a trait that fits well with her age. But being part of a criminal space team means she is not afraid to get her hands dirty. This video is one of her early moment: https://www.youtube.com/watch?v=0U_-SX1pPds