How to achieve power reading 3phase + solar feeding back to grid

Hi guys

I'm wondering how to achieve this

house is connected to 3phase grid.. so reading grid power consumption could be achieved easily with shelly 3EM

but i would like to read feeding back to grid from solar.. which is single phase..

what is the best way to achieve that.. get shelly EM?? but where do I attach it to???

So putting 1 x 3EM onto the main lines will give me both grid usage and feed back to grid?? Does it show as a negative value or actually recognises power going the other way and showing those values separately.. (been looking through internet but could not find any example)

Thank you