Thanks for the reply 877. Maybe I dont get it.You don't. You need to update to exFAT using ChoidujourNX, it can be done without updating firmware..
I have a 128gb sd card. My Switch is on 5.1 firmware. The switch can read exFat partitions fine but homebrew cant. If I format my sd card with fat32format then everything runs fine on my switch. Maybe I'm missing a crucial step?