I've had serious difficulty[1][2][3] with Apple's Notes.app over the past 18 months. So much so that I've written some JXA (Javascript for Automation) code to extract all of my notes to self-contained HTML files.

Now that I have 923 notes in HTML files on my hard drive, I can do whatever I want with them. My current plan is to import them into OneNote because they have good app coverage across platforms and they just released what looks like a pretty solid API that lets you import and export notes.

Maybe I (or somebody else) can write an importer for Standard Notes to make it easy to switch from Apple Notes?

[1] Notes not syncing across devices

[2] Search not working at all on Mac

[3] Moving subfolders of notes in the app makes the notes completely disappear