Here is a link to SavevVariables [SV, in short] (stores your settings of addons locally to your PC) describing how to find them, help to read them and how to backup them.
Maybe another thing that needs to be known about addons as SV should be backuped regularly (I recommand at least once a week) so you can go back to them easily.
https://www.esoui.com/forums/showthread.php?t=9235
They only change files if you reload the UI, logout or quit the game so if the client crashes they got an old unsaved state and you might loose data.
That's why having backups saves a lot of time, especially if you use addons that store data accross your toons, liek carfting and research related, and/or guild sales data etc.