Hello RolfG
No, the adapter is only for the VHS standard.
There are no such adapter cassettes from Video 8 to VHS, as this is not technically possible. The best way to preserve old Video 8 films is probably to have them digitised by an appropriate provider. This provider transfers the film to a USB stick or hard drive so that it can be viewed comfortably on a computer etc. It is even possible that the professional video 8 cassettes can be transferred to a computer. It is even possible that the professionally created digital film file will be of slightly better quality than the original, as age-related colour defects etc. can be digitally processed and reduced. Alternatively, you can search online for a suitable used player for the Hi8 tapes.
Regards
Andy from Hama