Hello,
I just answered you by email.
For the 3rd-party readers, I'll write this : Tennis Elbow 4 uses a peer-to-peer system for online play, as explained in the documentation =>
https://www.managames.com/tennis/doc/Te ... meCreation .
This means your IP address is automatically visible to your opponent and people who try to join your hosted matches : it’s how direct connections work.
That said, an IP address cannot reveal your exact street location, only an approximate city-level area. So there is no direct risk to your personal safety.