1. There's a app called https://www.exportnote.com which seems to do exactly what you are looking for. 15$ and you're safe.
2. You can import enex-files into OneNote and Apple Notes, which makes Evernote basically much safer than OneNote, as it allows you to switch easily if the service was discontinued all of a sudden.
If Evernote goes down, hello OneNote, hello Apple Notes, hello whatever. All data migrated without a hassle, and the least you get is time to sort out a future notes strategy.
If OneNote is discontinued ... well, good luck with exporting your handwritten notes which are part of a note and at the same time partly written over an image-file created from a PDF.
I'm not anti-OneNote, but I consider the issue of "what if it is discontinued" a much more severe problem with OneNote than with Evernote. I have to use OneNote at work, and I have no idea how I would ever be able to properly save the stuff if it was discontinued or if I changed employer and wanted to migrate large parts of my work into a system other than OneNote.
Evernote has a readily available OneNote- or Apple Notes-backup plan, which actually reduces the necessity to switch or to worry.