Hi Stacey,
Good news! Both The Events Calendar and Events Calendar PRO (and the Community Events, Eventbrite Tickets, and WooCommerce Tickets plugins too) can be translated to both English and French.
To get the plugin to work on both your English and French sites, you could purchase one license but install the plugin on both sites. You’ll have to attach the license to just one site (say the English site), but you can install the plugin on the other one too (the French site). It just won’t get automatic updates. You’ll have to do that manually by downloading it from our website and reinstalling it. You’ll still get access to the support and forums that way too.
Let me know if I’ve understood this correctly, or more especially, if I haven’t. If you have any other questions, please ask!
— Julie