Not sure I quite get how this works from the wall plug PoV: if you have smart metering on your electricity, will it actually show you drawing less from the grid due to the input provided by the panels to your local wiring etc?

Or is that it actually goes back to the grid and you would pay your bill minus the amount you’ve fed back in?

In Uk, If an old (rare) mechanical meter the meter will go backwards, the ideal. If a dumb digital meter the meter will simply pause counting up. If a smartmeter again the import reading will pause but a separate export reading will count up, for which you get no credit or debit but its nice to know. Ideally as battery prices drop you end up buying a battery that soaks up any surplus for later and so you don't lose any back to the grid. If you pay up for a commercially installed solar you can get paid for what you export but with plug in solar you just give it away.

You'd most likely need a different meter (and utility cooperation) to get credit for power supplied to the grid. These are expected to locally offset current use, so you pull less power through the meter, any surplus generation is a gift to the grid.

It is likely not going "back to the grid" unless you have the rest of your house shut down; where the "balcony solar" output is greater than your house usage. These systems are "back-feeding" into your circuits, and if you have it on a circuit that is less heavily loaded than the panels are providing, the other branch circuits are going to sop up that usage before it literally feeds back into the grid.