Para openSUSE Tumbleweed execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/home:StefanBruens:branches:KDE:Frameworks5/openSUSE_Tumbleweed/home:StefanBruens:branches:KDE:Frameworks5.repo
zypper refresh
zypper install plasma5-session
Para openSUSE Factory execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/home:StefanBruens:branches:KDE:Frameworks5/openSUSE_Factory/home:StefanBruens:branches:KDE:Frameworks5.repo
zypper refresh
zypper install plasma5-session