I am aware of at least the following options (including already mentioned):
- Zubax: Orel 20, Myxa, Mitochondrik, Sadulli, etc.
- VESC (also see http://vedder.se)
- Holybro Kotleta (based on the PX4 Sapog firmware), already mentioned by Jinger
- OlliW’s UC4H, already mentioned by David
- A reference design of an ESC from NXP supports UAVCAN: https://www.nxp.com/docs/en/brochure/Brochure-NXP-Suggested-Components-Drones-Rovers.pdf
- At some point I’ve been informed that Currawong Velocity support UAVCAN, but I can’t find any confirmation of that on their website, so this may not be true.
If you’re also interested in UAVCAN servos, see this discussion: https://github.com/ArduPilot/ardupilot/issues/8166#issuecomment-393935916