JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="ordename">
	<li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
    <li>Item 4</li>
    <li>Item 5</li>
    <li>Item 6</li>
    <li>Item 7</li>
    <li>Item 8</li>
    <li>Item 9</li>
</ul>

CSS

ul,li{margin:0;padding:0; width:300px;}
li{border:solid 1px #000;}

JavaScript

var orden;
window.onload=function(){
	orden=new Draglist('ordename',true);
}
var Draglist=function(target,identificar){
	var _this = this;
	this.target=document.getElementById(target);
	this.target.onselectstart=new Function ("return false")
	this.tgt=target;
	this.lastover='';
	this.encambio=false;
	this.flying=null;
	this.items = this.target.getElementsByTagName("li");
	for(x=0;x<this.items.length;x++){
		this.items[x].className=this.tgt;
		if(identificar==true){this.items[x].id=x;}
		this.items[x].onmousedown=function(e){drag(e);}
		         window.onmouseup=function(e){drop(e)}
		this.items[x].onmouseout=function(e){out(e);}
	}
	
					
	function out(e){
		if(_this.flying!=null){
			this.off1= document.createElement("li");
			this.off1.id= 'comod';
			e.toElement.onmouseout=null;
			_this.target.replaceChild(this.off1,e.fromElement);
			_this.target.replaceChild(e.fromElement,e.toElement)
			_this.target.replaceChild(e.toElement,document.getElementById('comod'));
			//e.toElement.onmouseout='';*Aqui es donde quiero devolver*
		}
	}
	function drag(e){
		if(e.target.className==_this.tgt){
			_this.flying=e.target;
			e.target.style.opacity='0.5';
		}
	}
	function drop(e){
		if(_this.flying!=null){_this.flying.style.opacity='1';}		
		_this.flying=null;
	}	
}