Rewrite value from one node to another one in a server |OPC UA Standard|Forum|OPC Foundation

I have a server containing an aggregate server and another node group. I would like to link the group nodes with the aggregated server ones. When a value changes in the aggregate server, the value is written to the other group. Not every node from the aggregate server is linked to a node from the group. I receive all nodes at runtime and a mapping that contais the nodeId to link togetter.

Do you know how I can do that internally on the server using C#? I try using references without success. Now, the only method I could think of is using a client to subscribe to the nodes and rewrite the values to the other nodes.

Sorry if it is a trivial question!