There are at least two artists/bands with this name.
These are photos from concerts where Wintersleep played, so they may be of other bands that played the concert as well.
Wintersleep Sep 17, 2019 Cologne, North Rhine-Westphalia, Germany Uploaded by Irene Neumann
Sonic Boom 2016 Sep 4 - 5, 2016 Edmonton, Alberta, Canada Uploaded by Jennasteeves91