Aphasia and dysphagia ( or asphagia) are two different things.
A person with aphasia has trouble speaking due to brain damage (usually a stroke). No supervision needed. Just patience and maybe visual cues to help person communicate. They know what they want to say, but can't get it out correctly
Dysphagia is difficulty swallowing due to brain damage (again usually a stroke). Supervision IS needed to prevent choking. They will have soft, maybe pureed, foods and liquids should be thick (or made thick). A person with dysphagia needs supervision any time they eat of drink.