After the UI update the old ability icons look blurry and low-res. You can use Clean Icons - Mechagnome edition which AI upscales all abilities in the game for much sharper resolution :
PhanxBuffs : Buff, Debuff, Spell : World of Warcraft AddOns
What enemy nameplate /buffs setup is this? What addon for health bar and what addon for buffs? : r/classicwow
Overview - Bison - Addons - Projects - WowAce
I need to find an addon that moves my buffs/debuffs under my character portrait : r/classicwow
How to disable buff icon next to nameplate - Tukui