This is how Sunset Shimmer meets Knock Out goes in My Little Pony: Equestria Girls: Rise of the Dark Spark.
[Sunset Shimmer walks out of the CHS entrance]
Sunset Shimmer: [to Derpy (EG) and Sandal Wood] Thanks again.
[As she walks down the steps, she sees a red automobile pull up]
Sunset Shimmer: Huh?
[Then the automobile transforms into Knock Out]
Sunset Shimmer: [in awe] Whoa.
Knock Out: [looks in her direction] Hmm?