I am not an expert on SQL Server, but I am not certain what you want to happen, or what you think should happen.
Do you want one database to be a copy of another? One database to update another?
Folders are a physical matter - there are files inside a folder. A database can exist on [or 'span'] different drives...........so folders are not really relevant.
Normally one connects to a database, not databases connecting to each other. Databases can 'talk' to each other but this is done via software, either via a database utility or software program.