Can scope mouthwash actually help with gingivitis, or does it just freshen your breath?

A little. It helps 'a little'. But your better solution is to get in the habit of brushing carefully/thoroughly(2 times a day) and flossing daily(i prefer at night before going to bed).
Mouthwash. In my opinion no unless it contains chlorhexidiene. Brushing for 5 minutes absolutely every surface of every tooth then brushing the gums (takes 5 min to be effective so time it) and flossing will cure gingivitis as you will be getting rid of all the bacteria that cause it and you will save a lot of money by not buying mw. In addition you will need regular check ups and cleanings so see yr dentist.