gorzka you are as obsessed with keeping gnome/gtk packages off your KDE the same way I'm obssesed with keeping KDE packages off my budgie...I respect that🙂.
it's odd the kde scanner will only scan one page--I used it in budgie a long time ago.
guessing I'd say the answer is 'no' because the of all the non-KDE solutions including gscan2pdf in flatpak (or is it repo?)
I don't remember skalite having those limitations but it's been a while
ps---even if it scans one page, I will sometimes use
pdfunite in CLI to marry them all up even if there's 20 single pages because evidently I love torture
gscan2pdf is ported to gtk circa 2018 and is the frontend to two CLI programs. it's in repo. I suggest this, it does multiple pages last time I used it--it's saved my a** a couple times when I had scanner plugin problems.