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Over - If Calibre Portable and the library folders are both located on NTFS drives (same or different) you could drop a Symbolic Link to the library folder into the Calibre Portable folder. Calibre will see the symlink to library folder as if it were the library folder.
You can create symlinks with the
MKLINK command, and here's what an NTFS symlink is ==>>
NTFS symbolic link - Wikipedia
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