Use the denote-project-notes package

The denote-project-notes by Samuel W. Flint makes it possible to associate a ‘project.el’ project with Denote files. The idea is to add directory-local variables to a project so that it can recognise note files therein. denote-project-notes defines commands to display project notes on the side.

Learn about the technicalities on the package’s webpage: https://git.sr.ht/~swflint/denote-project-notes.