For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:MargueriteSu:branches:M17N/openSUSE_Tumbleweed/home:MargueriteSu:branches:M17N.repo
zypper refresh
zypper install scim
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:MargueriteSu:branches:M17N/15.5/home:MargueriteSu:branches:M17N.repo
zypper refresh
zypper install scim
For 15.4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:MargueriteSu:branches:M17N/15.4/home:MargueriteSu:branches:M17N.repo
zypper refresh
zypper install scim