Changing directory or file names in the OS won’t affect metadata. Editing tags embedded in the file with an external editor or editing in Roon will. Edits in Roon are retained in the Roon database rather than in the file, so it is prudent to back up the database. The priority between tags, Roon imported metadata and edits can be user defined since 1.1. See:
Changes to tags should be picked up in real time, but the album/track Edit page has an option to force a rescan if that doesn’t occur.