Tesla Model 3 already can charge at almost 150 kW from Fastned's 175 kW CCS Combo 2 chargers. Will go to over 190 kW when upgraded to 350 kW.
As you can see on the chart below, Model 3 was able to charge at 130-150 kW between around 10% to over 50% state-of-charge, compared to just 125 kW previously (to less than 50% SOC).
Overall, the higher power should allow saving of a few minutes at the charger per session.
Fastned says also that this summer it will enable its first ABB DC fast chargers to charge at 350 kW, which should enable the full potential of the Model 3 at some 190-200 kW peak.