Communication via IP adress with Arduino IDE and ESP8266
You have the esp8266 talking.  Now you need to come up with a method of passing data from the arduinos to the esp.

You can use serial, you can use i2c, spi? Or something of your own design.  The problem wit using serial is the you are already using serial to communicate with the board from your PC.  You can use SoftSerial on the Arduino, but not sure how you'd do it on the ESP. 
There are ways of making both boards work as master and slave i2c and spi, but it's probably overkill.
You could use two pins, one pin sends a binary bit and the other to clock the data, set high when new data has been written and set low when it has been read.
Then just use the same sort of algorithm as you did between you eps.

I have assumed that one Arduino is connected to one esp.  Let the ESPs worry about ip addresses.  If you want the Arduino to specify the destination then use a simpler addressing system than IP and let the ESPs translate that.