You can easily use base64 encoding to send image data (in base64 format, as a text) to another player who can read this data (decode it) and load to his sprite object.
The most difficult task is to convert image to base64. Maybe trying to do it via JavaScript is the best way.
If you already have image endcoded in base64, you can use Sprite -> Load data from URL function, and paste it. :)
This ^ is not a full solution but it should help you ^^