How to setup two mysql servers with group replication to work individually, when no network

I have two mysql servers in two different places. Both servers must be able to read and write. All tables are designed to based on unique id (UUID) primary key. I want to sync these two databases live using a replication method when networks are available. But both servers must be able to work individually when networks are not available. Which replication method is suitable for this situation ? If someone has already tried this, please help me to resolve this problem. I have tried MySQL group replication, but when network disconnected i can only work on one mysql server which is bootstrapped. Othe one doesn't allow writes.