While Ciri doesn't have the genetic mutation aspect that the rest of the Witchers do, it's fair to say in both versions that this doesn't necessarily exclude her from being considered one of them, as her powers allow her an arguably greater fighting prowess than any Witcher mutation, meaning there would have been no ...

Does Ciri get mutations?

She trained as a witcher when she was young, but never underwent the mutations, so her swordplay is not bad. She just lacks the superhuman reflexes, speed and senses that the mutations give witchers.

Does Ciri get turned into a Witcher?

Ciri does undergo intense training to become a Witcher herself. She doesn't become a full-fledged Witcher during the events of Season 2. However, if Season 3 follows Ciri's fate in the books, she does eventually become a Witcher.