Here's a little adapter board for using Nano v3 shields with mega 2560 embed boards: GitHub - nagimov/mega2nano: MEGA2NANO adapter board allows using Mega 2560 PRO Embed boards with shields designed for Nano V3.
Whenever I did networking on 328p, 2kb of sram always forced me to count every byte. Anything http + encryption related (e.g. sending data to http endpoint along with HMAC digest) is pretty much impossible to fit into 2kb of sram. Since there aren't many shields available for mega 2560 pro embed, I've made this little adapter board. Now the best of both worlds come together and I get to use my nano v3 shields with whopping 8kb of ram 
