[Letho]

Depends on what you want it to do and how you define "cooldown tracker".

Thing is - TESO has no cooldowns (apart from several ICDs on procs).

If you want a generic addon for keeping track of all buffs/debuffs on you or your current target (=reticleover), i'd definetely recommend Srendarr. It comes along with a nice whitelist functionality for keeping track of very important auras (sadly not very customizable though).

I am currently developing an addon based on WoW's Weak Auras 2.

If you want a DoT/HoT - tracker (displaying buffs/debuffs on multiple targets without them fading once you change your target) - I don't think that sth. like this exists in this game. I'm not even sure if it's actually neccessary for the easyness of TESOs rotations.