I did it the easy way:

• copied link to browser then
• tapped on “Open in application?” from browser
• the above will work if you already have PeerTube app downloaded, no need to sign in.

Pasting the link to the search inside the PeerTube app didn’t work for me. I also tried typing “peertube.openrightsgroup.org/a/openrightsgroup/videos” and variations of, and still didn’t work.

EDIT: If you use Brave browser, you can add/save in ‘Playlist’.