Okay I gave the sd file a try just to quench my curiousity.
I successfully backed-up my cfw nand from my partition which is updated to the latest fw (and using latest atmosphere)
The folder structure is like this:
D:\Switch Backup\emummc\HPE0\eMMC
inside eMMC are the following files (nand split): BOOT0, BOOT 1, 00 01, 02, 03, 04, 05, 06, 07
inside emummc is a config.ini file with the following config:
[emummc]
enabled=1
sector=0x0
path=emuMMC/HPE0
id=0x0000
nintendo_path=emuMMC/HPE0/Nintendo
I know I am supposed to edit this and this what I did following the folder structure in the sdcard:
[emummc]
emummc_enabled = 1
sector=0x0
emummc_path = EmuMMC
id=0x0000
emummc_nintendo_path = Nintendo-emu
I then copied the latest atmosphere files in the sd card...
BUT, the switch boots to atmosphere but in sysnand (not in emunand), so there is something wrong with my config.
The linked tutorial about editing this in the link from the previous page is from 2019 and I was wondering if the structures in the config might have changed already. The link is:
https://gbatemp.net/threads/how-to-make-a-file-based-emunand-for-atmosphere.541810/
Can anybody point me to the right direction?
Thanks