Trying to trigger I/O action when return-power from "balcony power plant" exceeds total power

I am using Shelly EM3 to observe all three phases of my house, also showing the power I gain from my balcony power plant.

I would like to set an action, when the "returned power" from my balcony power plant exceeds the total power of the house.

On the I/O actions I can see that you may trigger the channels upon some limit, but I can't see any conditional triggering

upon some other channel.

Any ideas?