JSFiddle - React, Tailwind, and code Playground

HTML

<div><input type="file" id="a" multiple/></div>
<div><input type="file" id="b"/></div>
<div><input type="file" id="c"/></div>

JavaScript

var container=document.getElementById('a'),
		inputs=document.querySelectorAll('#b,#c');
    
container.addEventListener('change',function(e){
	var files=e.target.files,
  		tempFileList=null;
  if(!files.length)
  	return;
  
  tempFileList=Object.create(FileList.prototype,{
    length:{writable:false,configurable:false,value:1}
  });
  Object.assign(tempFileList,[files[0]]);
  
  console.log(tempFileList,files);
  inputs[0].files=tempFileList;
},false);