It’s the Cornish form of Guinevere. Nicknames include Jenny, Jenni, Jenn, Jen and Jenna.
Karl is the Germanic variant of Charles.
Carl is the Old Norse variant of Karl .
Shauna is the female form of Shaun or Sean, which are both the Irish form of John .
Jeanette is a diminutive of Jeanne.
Charlotte is the feminine form of Charlot, a diminutive of Charles.