I'll second what UNBROKEN has said. I have another set of 22" wheels I had on my 21 ST that has summer only tires on them, I would swap the factory 20's back on for winter and I never had to do anything but drive it for about a half mile and by then all my wheels were synced up with the car. When I had the tires mounted on the second set of wheels, I bought a whole set of ford racing TPMS sensors for 150 bucks from american muscle.
BTW way back in 13 my wife had a 2012 focus and my daughter had a 13, well the wife liked the dark stainless color of my daughters wheels and my daughter liked moms polished wheels so I swapped them and neither car needed training of the sensors, they just worked.