Dan Jolley 
Alex Unlimited, Volume 1: The Vosarak Code [EPUB ebook] 

Alexandra Benno can instantly summon parallel-dimension versions of herself. But these duplicates are always super-idealized: smart, fast, tough, and often the most beautiful girls in their world — while Alex herself is a clumsy, frizzy-haired wallflower. So when the government recruits Alex for top-secret espionage work, it’s always her alternate who gets the action, and, consequently, receives all the credit. Sick of being her own sidekick, will Alex be able to crack to Vosarak Code and complete her latest mission…or is she destined to live in her own shadow?