Location of external HDD

Within Libreelec /storage/.kodi/userdata there is a sources.xml this file contains all the paths to your media.

it'll contain something like this:

<name>Movies1</name>

<path pathversion="1">smb://192.168.1.10/Movies1/</path>

<allowsharing>true</allowsharing>

there will be a small bit of code like that for every share you have this is what tells Kodi where to look for your movies, TV, music etc.

Nevermind, misinterpreted the question...