Yes it’s Sunset Shimmer.
Yes she’s apparently the token ‘bitch’ character.
Because we totally need more movies about how apparently the most popular girls go out of their way to make the your life a living hell. Because they don’t have anything better to do with their time.
Honestly I think I’m only upset because I really liked the design of Sunset Shimmer, but now they’re making her the annoying mean character. Oh well.