https://www.thecarcrashdetective.com/3-across-car-seat-guide...
You need to look at the Peugeot 5008 or larger MPVs if you want that.
It's a gap in the market, I'd kill for a Model 3 sized car which was 5cm wider and had three proper seats in the back.
Source: the last three months researching and looking for the smallest car I can buy which can fit the whole family in.
It really does feel like a massive gap in the market, and I wonder why that is?
BTW, if you're still looking, and depending on the age of your kids, it might be worth looking at the MultiMac - it's basically a new back bench for your car, with 3x car seats built-in.
The ww Turan is also a option.
In the US kids who are small enough to need a car seat aren't going to be in the front (air bags aren't designed for kids)
ISOFIX points can be found in the outer rear seats and in the front passenger seat.
So then you most likely wont have space for the second parent.
Would all fit in a compact