You should put this in your child-theme functions.php:
add_action('after_setup_theme', 'replace_favicon');
function replace_favicon(){
if (method_exists('TC_header_main', 'tc_favicon_display') ){
remove_action('wp_head', array(TC_header_main::$instance, 'tc_favicon_display') );
add_action('wp_head', 'my_favicon');
}
}
function my_favicon(){
?>
<link rel="apple-touch-icon" sizes="57x57" href="/apple-touch-icon-57x57.png">
<link rel="apple-touch-icon" sizes="60x60" href="/apple-touch-icon-60x60.png">
<link rel="apple-touch-icon" sizes="72x72" href="/apple-touch-icon-72x72.png">
<link rel="apple-touch-icon" sizes="76x76" href="/apple-touch-icon-76x76.png">
<link rel="apple-touch-icon" sizes="114x114" href="/apple-touch-icon-114x114.png">
<link rel="apple-touch-icon" sizes="120x120" href="/apple-touch-icon-120x120.png">
<link rel="apple-touch-icon" sizes="144x144" href="/apple-touch-icon-144x144.png">
<link rel="apple-touch-icon" sizes="152x152" href="/apple-touch-icon-152x152.png">
<link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon-180x180.png">
<link rel="icon" type="image/png" href="/favicon-32x32.png" sizes="32x32">
<link rel="icon" type="image/png" href="/android-chrome-192x192.png" sizes="192x192">
<link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96">
<link rel="icon" type="image/png" href="/favicon-16x16.png" sizes="16x16">
<link rel="manifest" href="/manifest.json">
<meta name="msapplication-TileColor" content="#da532c">
<meta name="msapplication-TileImage" content="/mstile-144x144.png">
<meta name="theme-color" content="#ffffff">
<?php
}
then you need to change the hrefs with the correct path.
The correct path is where you uploaded the icons png files.
Hope this helps.