Yeah I already have Luma3DS + A9LH. Would like to make a backup of it. Just in case.Just follow the 3ds.guide if youre after a9lh+luma. It will make backups at the right time.
Otherwise Decrypt9 if your best option.
Curious question - is it really necessary to do a backup after successfully installing A9LH + Luma3DS? Or is the NANDmin.bin that is backed up before installing A9LH and Luma3DS already sufficient/enough?