I am only trying to make clear you were on the wrong path searching for a solution. As, after my first post above, you still were looking at output influencing settings, I tried to make myself more clear (because I apparently failed the first time). Nothing more, nothing less.
Then you will not be surprised that my advice is to declare it as such to your system at installation (or correct it using YaST > Hardware > Keyboard). When you did otherwise earlier, that then IMHO was wrong. That it then worked to your satisfaction, does not make it correct and sooner or later it might backfire. And it seems to me that that is now.
I am still on KDE 5 (and Leap 15.5, will not change for several month until all dust settles down) and thus can not say what and how the KDE Settings offer the end-user to mimic other keyboard layouts on the hardware for use.
As said, I mainly tried with my post to avoid you searching in the wrong way and thus getting more and more confused.