I think we've already established that es file explorer looks at the android side. We need something that will look at the librelec side. As I say, I know very little about libreelec but suggested you use the file manager on the libreelec Kodi menu bar under settings.
Best wait for a libreelec expert to get involved. However here is something on how to access libreelec files from a Mac.
https://wiki.libreelec.tv/accessing_libreelec#tab__sambasmb
In the meantime here is how I deleted some Kodi add-on leftover files on the CEMC fork. It may you can navigate a similar path using the librelec embedded file manager (following is copied from one of my posts on the Ares project forum). Replace references to CEMC with Kodi and covenant with duckpool.
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"Ok I fixed this.
I'm conscious that uninstalling an addon from within Kodi may not delete everything and remove all sources of possible database etc corruption.
So I tried something a bit more drastic.
Using a file manager, I first navigated to the .cemc/userdata/addon_data folder.
I deleted plugin.video.covenant
I then navigated to .cemc/Addons
I deleted script.covenant.artwork
Script.covenant.metadata
Plugin.video.covenant"
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