Not sure 'bout the Brake Buddy Advantage, but one thing to keep in mind with your Fusion Hybrid: Power (vacuum) braking is on ALL the time, even when ignition is off. That means, it is on whenever you are towing it, too. You need to make sure whatever braking system you get, will work OK with power braking on, and that this will not cause it to over-brake your Fusion and burn up the brakes.
I use the Readybrake braking system with our Fusion Hybrid, and it works great with it.
Also, with the Fusion Hybrids, regardless of braking system you use, make sure you run a charge line to the Fusion's battery. If you don't, you'll run the battery down within a few hours of towing, and will need a jump start when you get to your destination.
Will and Cheryl
2021 Newmar Baystar 3014 on F53 (7.3 V8) Chassis ("Brook")
2018 Jeep Wrangler JK ("Wilbur")