Doing some research on the designs before I posted this. It seems that the image in the last picture wasn't a coat of arms, it is the Centre section of Page 2 of the Codex Mendoa showing the founding leaders of Tenochtitlan.
I'll post a link, it's a fantastic read...
https://www.mexicolore.co.uk/aztecs/ask-us/rulers-white-dress
Posted via Steemleo