How to turn off app notifications vibration
Go to settings - sounds and haptics - system haptics and turn it off. This will turn off any vibration you receive while receiving notifications bro. do try and let me know if that helps.
How to turn off vibration for specific apps notifications how bro
Only if the app provides in app haptics disable we can do it bro. otherwise its not possible. only system wide disable will allow to stop receiving vibrations.