Hi there liquidflorian. Thanks for the note here. At this point we don't actually have such functionality in either plugin (beyond the Eventbrite Tickets add-on, which works with both free + PRO and allows you to have event registration in the form of free/paid tickets).
We have a CSV importer that's in the works, and will only work for PRO. But it will only allow you to import events into WordPress in the form of a CSV file, rather than export. You may want to try WordPress built-in export option, though, or see if a third-party plugin can help you out. Since events are just a custom WordPress post type, any CSV-export plugin that can pick up custom post types should work to some degree.
Hope that helps and sorry I couldn't offer up more. If you have other questions or need anything else please let us know.