Detect when a Plug uses less than 2 Watt for 2 Minutes with Homey Bridge and Beta?

i am using a qubino plug to load my phev with 220V at 0:00 with homey bridge only.
I want to detect when the car is full, e.g. when the plug changes power usage to less than 2 watts for more than 2 Minutes. Ideally I would use a countdown timer for this, but i am shocked , homey beta does not even support such a simple thing as a a countdown timer.
Any ideas how i could detect when no more power is needed and i can switch off my smart plug ? I mean it is a very simple requirement like detecting when the ebike is full, detecting when the washing machine is done and so on.

will delete this here and ask in flows forum