For Factory run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:michals:img/Factory/home:michals:img.repo
zypper refresh
zypper install installation-images-openSUSE
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:michals:img/15.6/home:michals:img.repo
zypper refresh
zypper install installation-images-openSUSE
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:michals:img/15.5/home:michals:img.repo
zypper refresh
zypper install installation-images-openSUSE