For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:rhabacker:branches:windows:mingw:win32:snapshots/openSUSE_Tumbleweed/home:rhabacker:branches:windows:mingw:win32:snapshots.repo
zypper refresh
zypper install mingw32-kmymoney5
For openSUSE Leap 15.2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:rhabacker:branches:windows:mingw:win32:snapshots/openSUSE_Leap_15.2/home:rhabacker:branches:windows:mingw:win32:snapshots.repo
zypper refresh
zypper install mingw32-kmymoney5