Publication/Subscription service for the Catalogue

It is briefly explained here: https://gaia-x.gitlab.io/technical-committee/architecture-document/federated_catalogue/. Does anyone interested in this feature? It can be easily implemented with help of some message broker, and publication part makes sense, but I'm not sure about subscription for FC. Ok, one FC instance can be subscribed for changes in another FC instance and can synchronise SDs in this way. But it's all depend on schemas registered in these instances, one instance may not accept SDs from another one.