Handling multiple instances of Event Store

I have setup an environment where there multiple instances of API server are load balanced. Now if those multiple instances of API server talking to their own instances of Event Store, how can those event store instances can be sync with the new addition of events ? However I always have this option multiple instances talking to the same instance EventStoreDB.

EventStoreDB cluster is meant for high availability.
a cluster can handle a lot of load for different services .
So no need to sperate on different cluster instances .