Katrina - the answer is no I have not. In fact I've only seen positive reactions between colonies.My son is planning a pico with zoas and RFA. I have not seen any warfare with zoas in my tank. Curious if you have?
The behavior I've observed most is zoa colonies adjusting to make room for new ployps. They even adjust their height to match the ones around them so they are all interconnected like gears.
Regardless of whether they are the same colony or a different colony, they seem to behave the same. The best example I have are between some blue eyed blondes and some magicians I have, they have aligned with one another completely.
My lights are still coming on, but when things open up I will post a picture.
Tell your son good luck with the pico! Sounds like an awesome plan to me.