Hi @tja,
this is not planned, nor it makes sense from the architecture point of view. The SysFS endpoints are generated from the Unipi kernel module, which is aware of the HW it is running on, but not aware of any peripheral devices.
The only way right now is the Evok, or you can directly poll the devices over ModbusRTU. We have some internal discussion from time to time about adding support for extensions to our ModbusTCP service. So far, no work has been done on that part.
Best regards,
Martin