do you wanna brick your reader with no way back?
have you read this: https://wiki.mobileread.com/w/index.p...ternal_storage
here's what I did: https://www.mobileread.com/forums/sho...3&postcount=48
I guess, partitioning with external tool like paragon over usb connection as described by rupor is possible, but you should pay attention on proper alignment of the partitions.
that's why I used fdisk via recovery console, which enables one to work sector wise.
also you must not mess up the boot area of the device, including the kernel / initrd partitions (mmcblk2p1 and mmcblk2p2). otherwise there will be no way to access the device anymore. there's a guy on the forum who destroyed his reader this way. irreversibly.
read this thread entirely: https://www.mobileread.com/forums/sho...=163137&page=2