I'm lucky in that I have a small solar panel setup (3kW) and battery system (5kWh) to go with it. With this battery set-up you really don't need appliance support - most of the advantages are accrued by force-charging the batteries to avoid mains usage at the peak cost period (usually around 5pm-7pm).
I also have a few smart plugs which turn things on and off based on the current price and battery charge - using Home Assistant, but that's mainly me just nerding about. Handy when prices go negative, though and my electric immersion heater goes on to heat my hot water tank
Notably Octopus is working on taking much of the complexity away. There is now an opt-in service for certain battery makes where Octopus will take control of the battery charginng and discharging, to minimise your bill. It will even generate you money by doing a force charge and discharge when the grid is paying premium amounts