Help suggestion with Honda Cr-z install rear seat?

I live in USA, they only have two seater. The rear is not seat but cargo storage unit. But in other country such as Asia and Europe they have 4 seaters in Cr-z. I'm gonna removed cargo storage to put seat in rear. I'm gonna buy it online from foreign Honda parts website then have it ship to USA. So my two little children can sit behind me in my Cr-z.

Question is what's like after I removed cargo to install seat with seatbelts? More room? More comfortable for children. I mean they do sit in back before but sit on hard plastic which uncomfortable for long journeys.

Or maybe it's best to leave the way it is and let children sit on hard plastic if you're saying won't make any better when put in regular seats in just like Cr-z in Europ

ARE YOU INSANE?
the rear area of the crz in the usa is NOT FOR PASSENGERS!
and you want your TWO LITTLE CHILDREN TO SIT THERE?!

"I mean they do sit in back before but sit on hard plastic which uncomfortable for long journeys."
- THIS IS ILLEGAL
- THIS IS DEADLY!
- IF THIS IS HOW YOU PARENT, YOU NEED TO HAVE YOUR CHILDREN TAKEN AWAY!

Additionally, there's NO WAY to add seats and seatbelts that you can ENSURE your children's SAFETY.

DO NOT PUT YOUR CHILDREN IN THE BACK AREA OF THIS CAR!
Buy a different car if you don't have a way to transport your children.