<?php

$tage = array("Sonntag","Montag","Dienstag","Mittwoch","Donnerstag","Freitag","Samstag");
$tag = date("w");

$wochentag = $tage[$tag];
echo $wochentag;

if ($wochentag="Freitag"){ echo do_shortcode("[metaslider id=11]"); }
?>