Not seen any gods online in a while so figured posting here a safe bet

From what could find on old forum:
To reset a profession to allow you to choose another ...
Reduce profession skill to zero
Remove 100k exp (same as for arch skills)
If Blacksmith reduce profession rank to 50% (one half)
If Craft reduce profession rank to 33% (one third)
If Harvest or Alchemist reduce profession rank to 25% (one quarter)


Can ask that profession reset on Zool so he can lose alchemy. Not sure if is switched over or if have to repick quest, but if the former if can have him as harvester please

Alchemy skill removed
Profession rank reduced from 20 to 5
100k exp removed.

You will need to earn the new profession (and the bonus exp that comes with it) as you would normally do in game.