WooCommerce - Custom Reviews tab content

functions.php

<?php

/**
 * Customize product data tabs
 */
add_filter( 'woocommerce_product_tabs', 'woo_custom_reviews_tab', 98 );
function woo_custom_reviews_tab( $tabs ) {

	$tabs['reviews']['callback'] = 'show_custom_reviews_tab_content';	// Custom description callback

	return $tabs;
}

function show_custom_reviews_tab_content() {
	echo '<h2>TESTING</h2>';
	echo '<p>You can put anything in this space...</p>';
}

?>