Hi Kai!
Thanks for reaching out to us. Let me answer each of your questions 🙂
does your addon also works with the german version of eventbrite (www.eventbrite.de)?
There is no limitation as to the Eventbrite language version you can use with the Eventbrite Tickets plugin.
Do i need the pro version of event calendar on top to use the add on?
No. You will only need our free version of The Events Calendar to use Eventbrite Tickets.
Did i understand it right, that if i using the eventbrite addon the only way to pay the event is paypal and google pay?
Payments for Eventbrite events are all handled by Eventbrite and not by our plugins, so the available payment methods are the ones that Eventbrite provides.
I hope that helps. Let me know if you have any follow up questions.
Best,
Victor