Doing this would require a lot of changes in the Jumping Sumo firmware:
- You will need to provide drivers to the 3g module, built for our Kernel (you can find our exact kernel here).
- The 3g module should have a public IP address, as the Jumping Sumo expect direct incoming connections
- If you can't guarantee this, you'll have to provide your own mean of association, like a STUN/TURN server.
- Using a non-wifi connection might be handled very badly by the stream monitor (the process in charge of tuning the stream bitrate according to the link quality).
So, tl;dr: You can, but it won't be easy.
An "easier" solution, if applicable for you, would be to use a bridge device (could be a smartphone), which will handle the 3G connection to your computer, and the wifi connection to the Jumping Sumo at the same time, with a custom build app to forward packets from one to the other.