In the words of Old Blood Noise Endeavors:

Realizing matching gaps in the market and their friends workflows, Old Blood Noise Endeavors unveils their newest utility device, the MIDI to Expression Translator (MTET). MTET is a simple device for complex workflows. It receives MIDI CC messages and turns them into expression outputs, allowing players to unlock MIDI control over their expression-enabled devices. Where once there was only a foot, now there is envelope control, LFO control, snapping to preset positions: any MIDI shape can express an OBNE (or similar) device.