Have a toggle mapped key, and use the: New Target Group Action

On Step 1, have your Mage join your Chloro group and leave the DPS group.
On Step 2, do the reverse.

Possibly also include a Pop Up Text action (Target: Current Window), on each step.
Just to let you know which group the toon in question is being placed in.



You'd likely want to combine this with two Do Mapped Key actions, in your spam key.
One for the Chloro Group, one for the Mage/DPS Group.
If you don't have toons in a group, it won't hurt to spam it as part of your spammed keys.
But since it is the same toon, The Mage/DPS might be:
Step 1 = 1
Step 2 = 2
Step 3 = 3
While the Chloro might be
Step 1 = 5
... because you want them to do their heals, or whatever, instead of the mage/dps moves.