While at NAB, I learned about the company Kiloview, and their NDI encoder solutions for video. Their N and E solutions allow for HDMI or SDI signals into an NDI receiving device. 

The E series is wired, while the N series is portable wireless.  Each device sends up to 1080p signals, and full H.264 encoding. Both series  also has USB and SD card support. They also weigh less than 1 lb. 

N1 and N2 feature 5G WiFi, and can be connected to Ethernet via USB. Unit holds an internal battery that is charged via 12V power supply. This unit can be hot-shoe to a camera. 

The E1 and E2 (wired solutions) are NDI|HX supported. HDMI loop support allows for video monitoring. 

Prices start at $565 (depending on product). Check out B&H for availability, or en.kiloview.com for more information.