Settings – Tap “Sound and vibration” 
Tap “Vibration intensity“
Reduce the vibration intensity for “Incoming call“, “Notification“, “Vibration feedback“
How To Reduce Vibration Intensity On Samsung Galaxy S7/Edge/S6/Note5/4
Settings – Tap “Sound and vibration”
Tap “Vibration intensity“
Reduce the vibration intensity for “Incoming call“, “Notification“, “Vibration feedback“