Problem getting/using Tuya plug state

I’ve got a few WLAN Tuya smart plugs, which work fine, and I control/monitor through LocalTuya. I have the relevant parts added in HA (1 for the switch, plus 18/19/20/23/25). I’m now working on a dashboard with some entity filter to just show certain active devices as well as open doors, etc. which works fine for everything that actually has a state - but somehow I can’t get a real sensor state for the Tuya plugs working …

I tried setting up some helper sensors like this:

- platform: template
  sensors:
    fernseher_state:
      friendly_name: Status Fernseher
      device_class: plug
      value_template: "{{ is_state('tuya_fernseher', 'On') }}"

but no matter what “value_template” I use to compare I can’t get the sensor to get any value than “unplugged” …

What am I missing / doing wrong?