Plumb the faucets in with some Frost Proof Anti-Siphon Outdoor Wall Faucets. You turn them off and there is no water in there.

https://www.homedepot.com/p/Merrill-...MAD8/308176700

Your next problem is the water that will be left in your P-trap. I guess you could plumb that into the basement and put the p-trap in the heated area of the basement.