Car seat help!!!

I need car seats that fit 3 across in my Nissan Murano. I have a 4 and 3 year old and they are currently in the Graco 4Ever seats. One car seat more will not fit with those bulky monsters. What car seats will fit in my car and accommodate and grow with my babies?! 😱 Baby girl isn't here until March 2021 but this has been the main thing stressing me out! Currently this has been my top choice just not sure if it will fit 3 across. It's either get a new car or 3 new car seats....so we are going with car seats 🤷🏻‍♀️🤦🏻‍♀️ HELP!