SongHe Mega2560 + WiFi R3 ATmega2560+ESP8266 32Mb Memory USB-TTL CH340G. Compatible for Arduino Mega NodeMCU for WeMos ESP8266

What are proper switch settings? Can talk to mrga 2560 but cannot program esp8266

Is it possible to purchase these boards without the headers soldered on?

What type of external antenna connector is used on this board?

do you have to modify the board, i.e remove a resistor to get the external antenna to work? Because just connecting one doesn't make a difference.