Yes I can tell you what I did to make it work.
First download the .rpm file and move it into another folder for example wps-office-2019.
With archive manager extract the content and there will be three folders: opt, usr and etc.

I usually mess up my system so I took the risk to do:
Right click to launch the terminal from the folder "wps-office-2019" and run:
sudo cp -r {opt,usr,etc} /
Thats all.

I recommend you to try it first in virtual box. Don't do experiments like me. :-p
You will see also an empty category "WPS Office" in the menu. It can be removed easily.

To remove all what you have done there are some more steps.

    evert Yes, version 2019 is more beautiful than version 2016, but it has a problem when switching from light theme to dark theme. I am writing from phone, so I can't post pictures. This issue has been since first release of v.2019 maybe because it is still Beta version. I suggest you to use v.2016. Both versions are way more faster than snap and flatpak versions, and system folders are more accesible.

      Well Algent,

      I do not know how come, but WPS 2019 riuns PERFECTLY. Many thanks. 😅 😅 😅

      Greetings, Evert Sonneveld

        evert Do you see an empty Category in Menu "WPS Office"?

        If yes remove it with:
        rm -f /usr/share/desktop-directories/wps-office.directory

        But you can keep it and use it to include WPS menu entries there.

          Reminds me, it'd be neat to be able to have some sort of subfolder system if possible within the Budgie start menu.

          @algent Gotta say you're really good at explaining this stuff in a simple manner and elaborating on things when asked. We need more people like you in this world w

          No, I do not have a empty Category. Anyway, I am very delightfull everyting runs perfectly. Thanks again.

          3 months later

          how did you make wps (the rpm version) the default for documents, spreadsheets and presentations?

            milomak Try to "Right Click" on the document and select there "Open With Other Application", and find there WPS (if you have installed it). Next time will be opened by WPS.

              winnie71 you installed wps using flatpak? the 2016 or 2019 version?

              edit - nvm. found it

                  2 years later

                  algent Good evening. It seems that this "trick" (sudo cp -r {opt,usr,etc} /) does not work any longer.
                  Would you know the reason for that?