I don't see why it couldn't be used with a bow, crossbow, or even a throwing weapon; I've always understood "weapon swing" to mean "an attack with a weapon", both melee and ranged, and I can't think of a Ritual effect that requires specifically a melee or a ranged weapon, so I can't imagine this would be the exception to that.
ETA: Poison Cache, Poison Trigger, and Potion Coating all require a melee weapon, but that makes quite a lot of sense considering their effects, as they all relate to coating weapons; there's no real point to putting Cache or Trigger on a throwing weapon, and you apply Poison to the arrows/bolts you fire and not the bow/crossbow, so there's no reason to put any of them on one of those.