Re: merge .meta and .shared files of different server
No, not at the file level.
I guess there may be a workaround for a set of shared files though: Create a new empty document in QV Desktop and publish it on your second server. Replace the Shared file that is created automatically with the Shared file containing the Server objects you want to copy from server 1. Now open the new document on server 2 in QV Desktop (Open in server...) and open the second document as well. Copy & paste Server objects from the second document into the new document that already got a set of Server objects from server 1.
In theory, your new Shared file should contain objects from both server 1 and server 2. I doubt if this works for Bookmarks...