Hello.
- Please note, the Google API is needed only for import of bookings from Google Calendar to the Booking Calendar. But this method does not support export of the bookings from the Booking Calendar to the Google Calendar.
You can find this info at WP Booking Calendar > Settings > Sync > “Import Google Calendar Events” page.
2) Export from Booking Calendar to other services possible with additional other plugin Booking Manager.
Please read more about this feature here: https://wpbookingcalendar.com/faq/#sync
Export.
Please check about the configuration of export .ics feeds in this FAQ instruction here https://wpbookingcalendar.com/faq/export-ics-feeds/
Booking Calendar is generated .ics feed with bookings in real time. But how often some services (like airbnb, or booking.com ) access this .ics feed to import the bookings from Booking Calendar into their own system, does not depend on the Booking Calendar. So in other words, Booking Calendar does not force the import process by third party service, when some booking is created. You need to check with support of this service (like airbnb or booking.com), about how often they can access the .ics feed for making imports.
Unfortunately, with Google Calendar it’s not the automatic process. Google Calendar can not automatically requests such .ics feed periodically to import bookings from Booking Calendar to the Google Calendar. So you will be need todo this manually relative to instruction from the Google Calendar settings.