It is hard to say as I can't see your swirls but, #9 is a very mild cleaner so it is possible it won't remove all of your swirls. Keep in mind that #9 is not a wax, you don't wipe it on and then wipe it off. Think of it more like a kitchen cleanser, you rub it in with a little elbow grease and then wipe it off. It may take repeated applications to remove your swirls.
As has already been said, you can apply NXT after #9 with no problems. Also NXT does NOT contain any wax. It is a polymer sealant. Wax is a very generic term these days.