I initially installed Mojave on an external USB3.0 HDD in order to avoid messing with the Win10 installation that's on the built-in M.2 SATA SSD. Given that the Latitude 7490 can boot from microSD card (needs Legacy boot enabled in BIOS), I installed Clover and the 7490 pack on an old 2GB microSD card I had lying around. Card was initially reformatted FAT32. I now use it to boot Mojave from a freshly created partition on the SSD without having had to mess around with the Win10 Boot (EFI) partition. It works great.