S8 was a much more expensive/premium device which had better overall features like display, camera and vibration motor. On the A20e, which is lot cheaper it uses a different kind of vibration motor which isn't as tactile, tight or strong as the s8 vibration motor. There is no way to increase the vibration strength on the A20e. Even a series like the a51/a72 come with worse vibration motors then the S8, and they only allow you to increase the strength of the vibration for system interactions, not for notifications or vibration on messages etc.
