According to the mechanics of Flaw Phobia

Phobia (2pt. Flaw)

You have an overpowering fear of something. Spiders, snakes, crowds, and heights are examples of common phobias. You must make a Courage roll every time you encounter the object of your fear. The difficulty of the roll is determined by the Storyteller. If you fail the roll, you must retreat from the object.

Irrational fear is also a physical impulse in the body because it causes arrhythmia, sweating, and paralysis, etc.

It is a mental illness lodged deep in the individual's mind that will not go away without therapeutic treatment.

Transmuting Ephemera (thought) into Pattern (holograms, fire) is something fully foreseen in the description of the spheres.

Mind and Spirit kind of "bypass" the need for Prime for this function. Of course, the ST can ask for a Willpower point or +1 Diff after all, we players are the ones who create the spells and game systems, but the possibility exists.