How to backport AddOns to WotLK? (whoa UnitFrames)

Hi! Good morning/afternoon/evening.

I open this post to check if any of you could help me in my task: I'm on the trail of 'whoa UnitFrames' for WotLK (3.5.5a). Apparently it doesn't exist.

This AddOn (whoa UnitFrames) has versions of it for versions of the game between 7.0.3 and 8.3.0. On the other hand, it has its corresponding versions for WoW Classic (in case it helps in my query).

Does anyone know how to do it to backport it to Lich King? Is it complicated to carry out? Would you like to help me, please? Thank you very much already!