JSFiddle - React, Tailwind, and code Playground

HTML

<div id="dates"></div>

JavaScript

var dates = ["Teen.Wolf.S04E06.Orphaned.31.07.2014.HDTV","Teen.Wolf.S04E06.Orphaned.07.31.2014.HDTV","Teen.Wolf.S04E06.Orphaned.2014.07.31.HDTV",
"Teen.Wolf.S04E06.Orphaned.31 07 2014.HDTV","Teen.Wolf.S04E06.Orphaned.07 31 2014.HDTV","Teen.Wolf.S04E06.Orphaned.2014 07 31.HDTV",
"Teen.Wolf.S04E06.Orphaned.31/07/2014.HDTV","Teen.Wolf.S04E06.Orphaned.07/31/2014.HDTV","Teen.Wolf.S04E06.Orphaned.2014/07/31.HDTV", "Teen.Wolf.S04E06.Orphaned.31-07-2014.HDTV","Teen.Wolf.S04E06.Orphaned.07-31-2014.HDTV","Teen.Wolf.S04E06.Orphaned.2014-07-31.HDTV"];

for(k in dates)
    document.getElementById('dates').innerHTML += dates[k]+" --> "+getDate(dates[k])+"<br>";

function getDate(d)
{
    var day, month, year;
    
    result = d.match("[0-9]{2}([\-/ \.])[0-9]{2}[\-/ \.][0-9]{4}");
    if(null != result) {
        dateSplitted = result[0].split(result[1]);
        day = dateSplitted[0];
        month = dateSplitted[1];
        year = dateSplitted[2];
    }
    result = d.match("[0-9]{4}([\-/ \.])[0-9]{2}[\-/ \.][0-9]{2}");
    if(null != result) {
        dateSplitted = result[0].split(result[1]);
        day = dateSplitted[2];
        month = dateSplitted[1];
        year = dateSplitted[0];
    }
    
    if(month>12) {
        aux = day;
        day = month;
        month = aux;
    }
    
    return year+"/"+month+"/"+day;
}