Since Amazon's Echo Dot 2 can control the Belkin's WeMos why not emulate it with this Esp8266 .
ESP after is connected to the WiFi network will start an UDP server on address 18.104.22.168 port 1900 and an HTTP server on its own IP address and port 80. Alexa on "Alexa, discover my devices " will send UDP on multicast address/port and the ESP will reply with its configuration (IP/PORT).
Echo Dot 2 will get the setup.xml from ESP on provided IP and Port.
From now on the Echo cand send SendBinaryState command that will end up in trigger a GPIO.
SSDP protocol is used in the discovery part.
And a video controlling 2 GPIOs with on one ESP8266.