nmrpflash uses Netgear's NMRP protocol to flash a new firmware image to a compatible device. It has been successfully tested with various models (D7000, DNG3700v2, EX2700, EX6100v2, EX6120, EX6150v2, ...
The Nighthawk M6 Pro mobile router has multiple models. See: https://www.rvmobileinternet.com/netgear-releases-unlocked-all-carrier-nighthawk-m6-pro-5g-mobile-hotspot ...