Stateful views in SQL Server
You could set up transactional replication from your main server to the server on which the views are materialized, and then, use a non materialized or materialized view based on their independent merits

More info:

You have server A and Server B, with A hosting DB A and B Hosting DB B

Now, you can configure transactional replication between A and B in such a way that Server A will have 2 Databases: A and B_Repl , similarly B will have B and A_Repl

The REPL databases are essentially an updated copy of the source databases. You can find many guides on how to configure replication on SQL Server

Once you have done that, you can create views on server A, and when you need to refer to database B, you refer to B_Repl instead. Similarly for server B