Merging Libraries
I have several music libraries on my PC. How do I merge them to one location?
iPhone 8 Plus, iOS 12
Question marked as
Open each library in turn and make sure the option to share the iTunes Library.xml is enabled under Edit > Preferences > Advanced or use File > Library > Export Library. Choose the largest library, or at least the one that has enough space on the drive where the media folder is to take the additional media, then import each of the XML files from the other libraries. Consolidate the resulting library. See this post on duplicate songs to clear up any duplicates.
See also Make a split library portable - Apple Community and Backup your iTunes for Windows library with SyncToy - Apple Community.
tt2