Change of playlists to Force relative path

[pip_pill]

I am moving around my MM library/music to use standalone on a laptop with external storage (4TB) rather than my home set up desktop connected to a NAS.
I copied the music and the library with playlists (which are all in a separate folder in the music folders) but the playlists don't work in the standalone setup..
I have a brief understanding of "Force relative path" option which I believe will allow the playlists to be transferred/copied to the standalone scenario and find the playlist tracks.
My question is, when I change the setting in MM the NAS attached situation "options" from unchecked to checked for "Force relative path" will this change the playlists currently already created or is there something I have to do to change the current (NAS) playlists to relative path, so I can copy the playlists to the standalone scenario and they will work?
ie So I can copy the playlist to the standalone scenario and the library/playlists will find the tracks?

[Lowlander]

It doesn't affect Playlist files that already exist, it only changes how newly exported Playlists will be created.