Instantly transform game object a to game object b's transform.

What i want to do is to directly map two objects together same exact transform without any movement transition, how would i do this?

The only way to do this (AFAIK) is to add a script to your object A and implement the LateUpdate function :

// Drag & Drop other gameobject here
public Transform otherTransform ;
private Transform myTransform ;

private void Awake()
    myTransform  = GetComponent<Transform>();

private void LateUpdate()
    myTransform.position = otherTransform.position ;
    myTransform.rotation = otherTransform.rotation;