When I saw the original question, I was not aware that @benhutchison was asking for implementation help (I thought this was just about the absence from the standard library).
Otherwise, my answer would have been the following which imho outsmarts the ChatGP solution:
given orderingForNamedTuple[N <: Tuple, V <: Tuple: Ordering]: Ordering[NamedTuple[N, V]] =
Ordering.by(_.toTuple)