Questions on using ipfs-clusters as seed nodes

I’m trying to deploy ipfs-clusters to provide permanent storage and seed ipfs nodes for client users who contribute and consume contents. Say, 2 clusters, cluster-A locates in US and cluster-B in Asia.

Here are my questions,
1, how can I guide US and Asian users to use cluster-A & B respectively?
2, when a US user shared a file and cluster-A pinned it, how can I order cluster-B to pin it as well?