Wiki which claims that there is binary release for Mk II is lying. You have to compile your own.

https://github.com/inversepath/usbarmory-debian-base_image

dpavlin@klin:~/usb-armory/usbarmory-debian-base_image$ ls -al usbarmory-mark-two-debian_stretch-base_image-20191013.raw
-rw-r--r-- 1 root root 3670016000 Oct 13 13:30 usbarmory-mark-two-debian_stretch-base_image-20191013.raw

dpavlin@nuc:/mnt/klin/home/dpavlin/usb-armory/usbarmory-debian-base_image$ dd if=usbarmory-mark-two-debian_stretch-base_image-20191013.raw of=/dev/sdb bs=1M

dpavlin@nuc:~$ dmesg
[764607.538898] usb 2-1: new high-speed USB device number 34 using xhci_hcd
[764607.689068] usb 2-1: New USB device found, idVendor=0525, idProduct=a4a2, bcdDevice= 4.19
[764607.689078] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[764607.689082] usb 2-1: Product: RNDIS/Ethernet Gadget
[764607.689100] usb 2-1: Manufacturer: Linux 4.19.78-0 with 2184000.usb
[764607.900916] cdc_subset: probe of 2-1:1.0 failed with error -22
[764607.902622] cdc_subset 2-1:1.1 usb0: register 'cdc_subset' at usb-0000:00:14.0-1, Linux Device, ae:47:47:81:a0:a4
[764607.902666] usbcore: registered new interface driver cdc_subset
[764607.902711] cdc_ether: probe of 2-1:1.0 failed with error -16
[764607.902732] usbcore: registered new interface driver cdc_ether
[764607.914234] cdc_subset 2-1:1.1 enp0s20u1i1: renamed from usb0

dpavlin@nuc:~$ sudo ifconfig enp0s20u1i1 10.0.0.2 netmask 255.255.255.0

dpavlin@nuc:~$ sudo iptables -t nat -A POSTROUTING -s 10.0.0.0/24 -o eth0 -j MASQUERADE

dpavlin@nuc:~$ ssh usbarmory@10.0.0.1
# password is usbarmory

usbarmory@usbarmory:~$ uname -a
Linux usbarmory 4.19.78-0 #1 PREEMPT Sun Oct 13 11:05:18 UTC 2019 armv7l GNU/Linux
usbarmory@usbarmory:~$ cat /proc/cpuinfo
processor	: 0
model name	: ARMv7 Processor rev 5 (v7l)
BogoMIPS	: 109.09
Features	: half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xc07
CPU revision	: 5

Hardware	: Freescale i.MX6 Ultralite (Device Tree)
Revision	: 0000
Serial		: 0000000000000000
usbarmory@usbarmory:~$ free
              total        used        free      shared  buff/cache   available
Mem:         512204       25588      436744        7624       49872      467984
Swap:             0           0           0

Switch near sdcard select booting from emmc or microsd (silkscreen is somewhat poor, but by default bafore removing sticker it will boot from sdcard)

Password for image delivered with device is not usbarmory (?)