So I did my research on this issue, and it seems like the top 'fixes' for this issue were including the OneDrive, and another AddOn folder in the C: Drive. The OneDrive situation doesn't apply to me, since ESO doesn't even have a folder in there. I -do- have an extra AddOn folder in my Program Data Folder, but the game isn't looking there, since the only AddOns that I have installed currently are SkyShards and LoreBooks.
My Path is as follows: C:\Users\NAME\Documents\Elder Scrolls Online\live\AddOns as it should be. However no matter what AddOn I download into this folder, no addons show up at all, and it's frankly frying my mind trying to figure out why. My actual game files are on my E Drive in my Steam folder, and I've tried moving my addons there, the OneDrive, and the Program Data folder to see if it changed anything, but to no avail. Please offer any insight you all might have into this issue.