kcharselect from KDE:Applications:18.04 project
Select Your Operating System
Add repository and install manually
For openSUSE Leap 15.0 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/KDE:Applications:18.04/openSUSE_Leap_15.0/KDE:Applications:18.04.repo zypper refresh zypper install kcharselect