> Remove from the motor/base, separate parts, spray with water

And then do in reverse once it's clean. And you're wondering why it seems like too much trouble...?

Plus you still need the knife and cutting board anyways to chop off the ends of the onion before peeling it. So it's not even instead of, it's in addition to.

Much less time to dice it yourself for one or two onions. Ten or twenty onions, OK it's food processor time.