iCagenda is able to export event in ics format (for Outlook, iCal... import).
And with online add to cal for Google Calendar.
This is currently only an option for frontend, with the Add to Cal feature of iCagenda.
But iCagenda does not have today any system to link an external calendar to its own calendar so no export/import functionnality.
Hope this answers your question? (the answer is no)
Latest version : iCagenda 3.8.21
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