I mean if i could make a list.
From classic that would require basically full on rebuilds
Scholomance ( more like the original scholo)
SFK (new storyline/mechanics)
Deadmines (new storyline/mechanics)
from TBC that would require re-tooling
shattered halls
The mechanar
Shadow labrynth
From Wrath
Halls of reflection
Gundrak
HOL
from cata
stonecore
Vortex pineapple
ZA
ZG
from mists
Siege of nizao
stormstout brewery
gate of the setting sun
From wod
skyreach
from legion
Blackrook hold
vault of the wardens
return to kara
stea of triumverate
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i consider BFA and SL to be still to ''new'' to be considered old dungeons.