How can I link my Roon profiles to the respective Qobuz users when I have a Qobuz Studio Family subscription and use Roon, where Qobuz is one of the music streaming services
In Roon, I have created multiple user profiles, but there’s only one login for Qobuz. Currently, only one of the family users gets their music displayed in Roon, regardless of which profile I choose in Roon.
Is it possible to solve this so that each Roon profile is linked to the corresponding Qobuz users?
In short, you cannot 
You can only use one Qobuz (or Tidal) account within Roon.
You can vote here for it 
Voting is unlikely to help something that the services don’t offer via the APIs. Family accounts are not available to 3rd parties. Even if they did it would require a fundamental change to how Roon manages its library, can’t see that happening easily. But vote away.
With Sonos I believe you can, but that’s a Sonos thing 
Not handled the same at all. Think about how Sonos works, then think of how Roon works. Very different beasts and it’s not working in the same way at all.