Hello, I noticed that there is a plugin for Obsidian called Booksearch. It allows you to search for books by title, ISBN, author, etc. I haven't found anything comparable for Joplin.
The same goes for the Bases plugin.
I find both plugins very interesting and would like to have them for Joplin as well. Maybe someone has the inspiration to create them? Perhaps the core of Obsidian could be used? Unfortunately, I can't program (I wish I could). But if I can help in any way (even with a small financial contribution if necessary), I'd be happy to do so.