If your total power flow is measured by the smart meter take sensor.solarnet_power_grid as Combined Entity.
If one of your inverters is not going through your Smart Meter, then you need to create a template sensor with the calculated sum.
Home should be calculated from the difference, but sensor.solarnet_power_load is also doing that.
For the Solar did you take the sum or just top one is inverter 1 and bottom one is inverter 2?
If the second option, then the calculation is wrong, as the top one wont be looked at. You need to sum them and set as the bottom entity