An experienced defender and former captain of Linkopings, Janni’s club achievements include winning the Elitedivisionen - the top tier of women’s league in Sweden - and the Damallsvenskan - the top flight women’s league in Denmark - twice.
Janni is a Denmark international, having played at under-17, under-19, under-23 and senior levels.
Joe Montemurro said: “Janni is an experienced professional and an important addition to our squad. Her understanding of the game, technical knowledge and game experience is important for our squad to grow. We are pleased to have her with us and I am looking forward to working with her.