Hi, I have an earlier base model with no alarm, so cannot really help you, I hate the noisy things anyway >
But I have part of the 2018 manual here and the movement interior sensors can be switch off in reduced guard mode instead of full guard. If someone does not answer you soon on how you select reduced guard mode, then go to Ford dealership and ask a salesman.
Full and Reduced Guard
Full guard is the standard setting.
In full guard, the interior sensors are on when you arm the alarm.
Note: This may result in false alarms if animals or moving objects are inside your vehicle. Reduced Guard
In reduced guard, the interior sensors are off when you arm the alarm.
Note: The alarm will reset to full guard the next time you switch the ignition on.
Ask on Exit (If Equipped)