Most of the time when I hover over buffs on Enemy frames it shows the wrong buff/icon.

For example, this hunter is running around with a priest so he does most likely have a Stamina Buff, but when I hover over it I see Wyvern Taming Wand...

The same thing happens when fighting for example the Alliance bosses (pvp event) in Ashenvale, it shows a thorns icon but when I hover over it's some buff that makes the Boss do more damage etc.

I have your latest version (4372), but I remember this being a bug in Classic (2019) as well

note that this does not occur when hovering over Friendly players/npcs

This is caused by missing SoD spells in LibClassicDurations