Hello,
I have a Wago PLC also.
For me the PLC is always the “boss”. So all switches and commands are on his control.
HASS is only used to bypass the controls. As such I am always sure that my automation is working even when my HASS is down.
It took me a while to get it configured as I am not a modbus expert. But I found quite some weird things with the implementation in HASS…Not sure however if this is due to the python script or a different “implementation of the modbus protocal of wago”. However this link may help you to get past some strange behaviours : Modbus sensor
As far as I understood the python script controlling hass has also recently be changed…I had no time yet to install the newest version of hass 46.1 (Switch pymodbus to pypi (@andrey-git - #7677) (modbus docs))
Hope this will “revamp” the modbus discussion in HASS.
Regards
hschroyen