1. the only way I have found is to duplicate the folders on my hard drive and save each file to that folder.
2. as you say just save to usb overwriting the previous. A better idea is to have 2 and save to them alternately.
Best phone camera 2017
Stunning new film posters by Hattie Stewart, Joe Cruz & more
iPad Pro 10.5in (2017) review
28 astuces pour profiter au mieux de votre iPhone