For my part, I reverted to the "legacy version" for now. When the day comes that the legacy version is no longer supported, I will cancel my EN subscription (sadly, because before EN 10 it was EXACTLY the tool I needed, with all solutions being inferior).
I've already tested OneNote... while not as good as the legacy Evernote, it is still way better than Evernote 10, so that's probably where I am going to migrate to when the day comes... Of course, disabling the spell checker is possible there, among many other settings.