Mega +WiFi R3 Atmega2560+NodeMCU ESP8266 32Mb Memory USB-TTL CH340G Compatible For Arduino Mega is Full integration on one board Mega R3 ATmega2560 and WiFi ESP8266 with memory 32Mb.
All of the modules can work together or separately. And everyone has their own pinout headers. The convenient solution for the development of new projects requiring Uno and WiFi. Via USB you can update sketches and firmware for ATmega328 and for ESP8266.