Yermek

const user={
  id:1,
  name:"Юрий",
  group: 123
}

const keys= Object.keys(user).map(function (k){return k});

function changeProp(obj, prop){
  obj["_"+prop] = obj[prop];
  
  function getProp() {
  	return "=="+this["_"+prop];
  }
  
  function setProp(value) {
  	this["_"+prop]=value;
  }
  
  getProp.bind(obj);
  setProp.bind(obj);
  
  delete obj[prop];
  Object.defineProperty(
  	obj, 
  	prop, 
  	{
  		get: getProp,
  		set:setProp
  		},
  	)
}

keys.map(
  function(key){
    changeProp(user, key)
  }
  )
  

console.log(user.name)
user.name='Bad Man';
console.log(user.name)

==Юрий
==Bad Man