Das Vermächtnis der Wandler (The Legacy of the Shifters).
After the events of the first six books, Carag and his friends face new challenges as they mentor younger shifters while dealing with lingering threats from those who oppose their kind. The Wider "Walker" Universe Brandis, Katja 7z
Carag, the cougar-shifter, returns as the lead character. Das Vermächtnis der Wandler (The Legacy of the Shifters)
Clearwater High, a secret boarding school for shapeshifters. Brandis, Katja 7z
The "7z" in your request likely refers to the in her overarching walker universe, which is the first book of the sequel series: Woodwalkers: The Return (Season 2), Volume 1: Das Vermächtnis der Wandler (The Legacy of the Shifters).
Brandis has built an extensive world through several interconnected series: