While debugging everything Shelly, I traced that voltage changes are not being sent from the Shelly to HA on ws notifications. The logs show only aenergy and ret_aenergy. The Shelly documentation does not clearly define what measured variables are sent in a NotifyStatus notification (as compared to the full detailed NotifyFullStatus. I did find https://shelly-api-docs.shelly.cloud/gen2/Component…#webhook-events which writes webhook events only fire when the voltage changes at least 1V and at least 5% from the last reported value.
But... this is voltage....230 volts. 5% is +/- 11.5v. So if Shelly's internal logic is to only send webhooks (and likely notifies) if the voltage goes lower than 218.5v or higher than 241.5v ... that's just too large a range in which to send no voltage notifications.
Similar rules apply to current; at least 0.05a and 5% from previous value. However, this might be more reasonable for amps.
I see the Shelly integration system option for polling was already set on install to be TRUE. But I don't see evidence of polling in the debug logs (attached below)
Manually curl to the shelly correctly returns voltage
Home Assistant Shelly integration related bug at https://github.com/home-assistant/core/issues/111598