Eaton, has been the main NUT supporter in the past, between 2007 and 2011, continuing MGE UPS SYSTEMS efforts. In 2022, the Eaton NUT-based companion software bundle sources developed (pre-?)2013-2018 were contributed and re-licensed to become part of NUT. As such, Eaton has been:
supporting its customers using NUT.
The situation has evolved, and since 2011 Eaton does not support NUT anymore.
This may still evolve in the future.
But for now, please do not consider anymore that buying Eaton products will provide you with official support from Eaton, or a better level of device support in NUT.
Powercom, through Alexey Morozov, has provided extensive information on its USB/HID devices, along with development units.
They also have a page suggesting NUT as the software to support a wide range of their USB HID capable models.