I can't be totally agree with you.

Trial on HP Probook with Debian MX-Linux 25 with XFCE works fine without change

How? Is the same machine, with the same user but under different desktop (XFCE in place of KDE) or is totally different?
After trying out different operating systems, I decided to stick with Debian + KDE for the last 15+ years.
I have to admit that I've encountered some problems at times, but I think that's because I like to keep up with the latest developments (the test version).

1. Few months ago I've encountered the same problem as you but I've solved only renaming .eteks/sweethome3d to .eteks/sweethome3d-old.
Than I've start SH3D, I've modify settings from inch to cm and close.
In the newly created .eteks/sweethome3d I've copy from the old what I've need.
As you could see it work with Wayland as with X11.
2. I've seen what you've purge and I think now even Libre Office don't work.
3. SH3D work best with their embedded java 8 and java3d-1.6.2a.
4. About Plugin Manager Keet have right. To make it work it need to replace jre1.8.0_202 with jre1.8.0_471.