Raspberry Pi Zeros are brilliant. By running them in Ethernet OTG mode, you literally only need a Micro-USB cable to control them. The guide to follow is this one, you literally follow them verbatim. However if you want to have stable MAC address, you need the following kernel options in ''/boot/cmdline.txt:
g_ether.host_addr=72:8d:1f:c4:e8:ca g_ether.dev_addr=46:10:3a:b3:af:d9