Just to be clear, this isn't a special property of Floral Healing or anything. You can freely hit your allies with priority moves even during Psychic Terrain.
I had heard a lot of people saying the opposite in Showdown, but wasn't entirely convinced. It is good to know that Comfey can still heal a Tapu Lele ally then.Tested O-wing, Strength sap (triage), swagger, taunt, and heal pulse (prankster) all work in psychic terrain on allies only. Also, ally dark types can be hit by a status move used by a prankster user (used the same 3 moves).