downhill as to that post...I thought it strange the OP (@toniohelpdesk) had an older computer that needed the proprietary plugin and nothing would suffice. You are right, I had not considered that since it worked for him/her on other distros.
Then I remembered I had to do this for an Epson scanner. Twice. My post was called (no luck with epson scanner or something,)
If this OP and the tonio op are reading you might need the whole package the plugin came in--preferably deb because that worked for me on the epson end.. And selected files to copy into Solus. And moving. And copying. And symlinking. And permission handling. And after much agony I wrestled that proprietary plugin into Solus. And you might have to research.
One of the hardest things I ever did, digitally, and forum members (telios and axios) helped me.
In event no one at Solus Forums have ever got this exact plugin to work, then research--you will find the answer and maybe a tutorial. If I got a proprietary scanner plugin installed and functioning with my Epson scanner and epson linux package (utsushi) than anyone could. I'm not that bright with a lot of things.I think it's a do-able venture--and I don't know how to go about it since I have no HP stuff---and it may require many ibuprofen--and I may be completely wrong.
here's to hoping someone here has succeeded and can share with you. edit/typo