Alterjack, or AUjack, or AUJ, or Alternate Applejack, or in her home universe, just Applejack, was a late addition to the series who came into the main Princess Applejack world after Sunset Shimmer's experiments with her portal mingled with leftover chaos from Fluttershy and Discord's battle. Lost and adrift, she immediately made her way to Canterlot to seek out that universe's version of her. And tear her world a new one for everything it's got wrong with it.
She's tough as nails, she's pragmatic and direct to a dangerous degree, and she's not standing for any imperfections. She's a Princess, and she's the only goddamn one of them who knows that a princess has to do actual political stuff, in this universe or any other.