What .iso images are u trying to install?
From what I understood .iso images or .img images are for uefi which requires u to flash uefi to boot .isos from your usb… if you are trying that on the edge 2… brather my experience sucked… I cant stand to loose oowow over the current uefi.
If what you want is Arch Linux please try this guide:
Panda and Kwankiu are and have been working on arch linux for the arm boards and they actually have working images on the most recent kernel 6.1 and 6.8 (however mainline is broken better stick to 6.1 or 5.10).
kwankiu is soon to make upgrades on our side and will eventually get it working perfectly.
Try pandaa image for now.
To all images all u need to do is basically put them into your usb into yourel edge 2 booting into oowow and selecting ‘all’ to see all files in ur usb and flash them.
Or armbian: