After recently switching from iOS to Android, I found that my Apple notes (of which I had many thousands, accrued over several years) were not easily exported to any equivalent platform on Android. Further to that, I found that most popular note applications on Android similarly prevent import/export.
One exception is the Standard Notes application and service, which provides client-side encryption for all notes, and free cloud syncing, with clients on iOS, Android, macOS, Windows and Linux. For that reason, I wrote this simple script to extract notes from the macOS Notes app database and convert them into the Standard Notes format.
This script will find all notes in all accounts, and generate a valid Standard Notes 'export' (which can be imported through the Standard Notes desktop app), preserving creation date, edit date, title and basic formatting. As Standard Notes doesn't support rich text/HTML rendering by default, the HTML structures used by Apple Notes for lists, titles, etc. will be converted into valid Markdown during export.
python3 apple_notes_to_sn.py <path_to_notes_db_file> will write out the Standard Notes export to Standard_Notes-apple_notes_export.txt.