Charging MacBook Pro in car

You can purchase power inverters that will provide 100W or even 150W. You need 100W at least. People camping get them all the time for computers and other devices. You plug them into the cigarette lighter port in the car. These devices cost under $30 and are somewhat noisy and throw off some heat but they do work. The USB car port is only for small devices.

98 watts USB-C port that supports USB-Power delivery at 20 Volts level ( i.e, forgetaboutit )

yes fifty times more power and hugely more Voltage and additional smarts.

Depending on what you’re actually doing w/ the MBP in your car, your power needs are likely significantly less than the full-spec’d power supply is designed to provide.

For instance my own 15” MBP draws about 18-20W doing “lightweight” tasks.

I’d suggest maybe trying a Belkin 36W USB-C charger to see if it meets your actual needs.

https://www.belkin.com/us/p/P-F7U013/

(They used to be carried in the Apple Store)

If you find it’s insufficient, you’ll still have a nice road-charger for your iOS devices.