If two global shutter cameras take a scene at the same time, they would have the same image. If they don't, then they wouldn't.
Global shutter cameras are also not new. CCD sensors are global shutter and we used to use CCD sensors for cameras decades ago until we switched over to CMOS for most applications due to their larger size and better dynamic range. I have a global shutter HVX200 from 2005 in my closet.