<?php

$re = '/[\p{L}0-9_.-]+@[0-9\p{L}.-]+\.[a-z.]{2,6}\b/u';
$str = 'Please email us at: some@example.com. You can also mail us at some@example.co.uk. Etc... hello@åä-ö.com
example@so.il.uk';
if (preg_match_all($re, $str, $matches)) {
  print_r($matches[0]);
}