I think a mod like this would be prohibited by blizzard. The mods that show mining nodes, herbalist nodes all have to start with Zero nodes in data base and can only mark, save and show nodes that the user has found once for himself.
Several people tried to provide mods with this information already in the data base or mods that 'mined' the data from the game from sources that did not require the user to have visited that node and blizz cracked on them.
So someone could make a mod that once you got a quest from an NPC marked that NPC as giving that quest for your future referrence but no mod can with blizzards blessing provide you with that info in advance.
Now alla can and does.