After reading the manual, it looks like the 2020 Explorer does all of these things. Below is what the manual states. The first applies to reverse, the second to drive. I've only ever experienced the "Alert" in drive, though I've never been close to an actual impact.
Reverse braking assist: If the system determines that a collision with an obstacle may occur, full braking may apply. Bring your vehicle to a stop a safe distance away from the obstacle.
Pre-Collision Assist System: The system is active at speeds above approximately 3 mph (5 km/h) and pedestrian detection is active at speeds up to 50 mph (80 km/h).
If your vehicle is rapidly approaching another stationary vehicle, a vehicle traveling in the same direction as yours, or a pedestrian within your driving path, the system is designed to provide three levels of functionality:
1. Alert
2. Brake Support
3. Active Braking
Alert: When active, a flashing visual warning appears and an audible warning tone sounds.
Brake Support: The system is designed to help reduce the impact speed by preparing the brakes for rapid braking. Brake support does not automatically apply the brakes. If you press the brake pedal, the system could apply additional braking up to maximum braking force, even if you lightly press the brake pedal.
Active Braking: Active braking may activate if the system determines that a collision is imminent. The system may help the driver reduce impact damage or avoid the crash completely.