As a yWriter user, I wrote a Python script that creates a new yWriter project from a CSV export file.
It is free and open source and has an easy-to-use drag-and-drop interface. There is also an Aeon 3 template based on Aeon’s Novel template that adds a “viewpoint” relationship to events and brings the required narrative numbering system.
To run aeon3yw, you need a Python installation preferably up-to-date.
You can find more information and the download link on my project homepage.