Via the Actions>Export to Apple App menu item you can choose to export metadata which is not stored in audio files by Apple applications but rather is retained in their databases. Note the operation only works on selected files which are linked. The values which get exported depends on the fields selected in Settings - Apple Apps - Fields of Interest.
Warning: If you are not setting the Maximum Grouping-Work Name Compatibility option, you should not export (or auto-export) the classical metadata. Exporting the Work Name field under this condition will cause you to lose your Grouping metadata. For this reason it is a good idea to not enable the classical metadata options in Settings - Apple Apps - Fields of Interest or Settings - Apple Apps - Auto Export.