You just need to set the path in the Settings -> Content -> Media -> Media libraries folder setting. Enter the folder location you want the system to store the files in. The location needs to be in one of the following formats:
- physical path - for example, c:\Libraries.
- root-relative path - for example, ~/Libraries. But this one will be inside the web root folder.
- UNC path - for example, \< server name >\Libraries. Note that if you want to use a UNC path while hosting your media library on a different server, you need to use the CMSAllowCheckIOPermissions web.config key set to false.
Then, if you will ensure the same folder structure of the actual media libraries in the new location, you should be good to go as the FilePath in the DB table Media_File will be the same - so no need to re-import the files.