We are using Akka with our java services to manage communications by putting the services in the same cluster. There is also a need to communicate with other services written in other languages (like python).
Is there a way that a python service could register itself in the same Akka cluster (as the existing java services)?
Implementing the Akka remoting and cluster protocols is not something that is actually reasonably doable, it is intended as communication between Akka nodes, not a public protocol for interacting with other types of languages/platforms/runtimes.
Such interactions should instead be done through explicit protocols, direct like for example HTTP/gRPC for request-response or streaming, or, as you mention, through a message broker, for decoupling or more event driven interactions.