On X11 and Wayland session, I have set the numpad lock ON at plasma startup. It works on X11, but on Wayland, I have to push the Numpad Lock key at every startup in order to get numpad working, even if it is ON in the keyboard configuration module.
My bug report about this https://bugs.kde.org/show_bug.cgi?id=375708
*** This bug has been marked as a duplicate of bug 375708 ***