That depends on which effects you are trying to duplicate. If its just to induce fear or a general hopeless feeling in the enemy, you just need to be able to give them the "Shaken" condition, which can be done numerous ways (as simple as an intimidation check).
If you want to do more than that, and potentially weaponize it, that's an entirely different issue altogether. Paralyzing, stunning, or even causing physical harm are not things that single abilities are versatile enough to do outside of spellcasting.
Aura of Doom is a 10 minute per level spell like that. Warpriest is an option that has it, but the Spiritualist with Phantom Blade archetype is even more Bleach-like.
There isn't an official answer if it has any of the limitations of black blade. But it appears that it does not, because of this ability:
- Does it have to be a one-handed slashing weapon, a rapier, or a sword cane (similarly to a Black Blade)? The description says, “A phantom blade begins play with an ectoplasmic sentient weapon known as a phantom weapon, whose weapon type is chosen by the phantom blade. The weapon type must be one with which the phantom blade is proficient. A phantom weapon functions similarly to the black blade of the bladebound magus archetype.”
Reshape (Ex): At 7th level, a phantom blade can change the weapon type of her phantom weapon when she refreshes her daily spells.
- Does the weapon need to fulfill any specific prerequisites for enchantments? For example, disrupting can only be placed on a bludgeoning weapon, so can I still apply disrupting to a Phantom Blade if it’s in the form of a sword?
That's a good question and I'm not sure. I do have to think there was at least an intention that you could put disruption on your slashing or piercing weapon though, because it gives you that option and the archetype is called a phantom BLADE. It's entirely possible that the writer simply forgot that disruption is bludgeoning only. Sometimes intention doesn't match RAW.