Headphone jack iPhone 7. Charger case

Hi I’m thinking of getting an iPhone 7. I currently have the 6 and use a charging case. I know that the iPhone 7 doesn’t have a headphone jack for some stupid reason but anyway. I was wondering as the case that I want for the iPhone 7 is also a charger case and the only port is a micro usb (at the bottom of the case) would I be able to get a micro usb to headphone jack and then connect a normal 3.5mm headphone cable into it. Would this work? If not please recomend a chagering case that I can connect a headphone jack into or an adaptor. I hope this makes sense?

Thank you.