functions-6.1.2.php

function fusion_get_related_posts( $post_id, $number_posts = -1 ) {
	$args = '';
	$number_posts = (int) $number_posts;
	if ( 0 === $number_posts ) {
		$query = new WP_Query();
		return $query;
	}
	$args = wp_parse_args(
		$args,
		array(
			'orderby'             => 'rand',
			'ignore_sticky_posts' => 0,
			'posts_per_page'      => $number_posts,
			'post__not_in'        => array( $post_id ),
		)
	);
	// If placeholder images are disabled,
	// add the _thumbnail_id meta key to the query to only retrieve posts with featured images.
	if ( ! Avada()->settings->get( 'featured_image_placeholder' ) ) {
		$args['meta_key'] = '_thumbnail_id'
	}
	return fusion_cached_query( $args );
}

functions-6.2.0.php

add_filter( 'fusion_related_posts_query_args', function( $args ) {

	// Remove same categories condition.
	unset( $args['category__in'] );

	// Set orderby to random.
	$args['orderby'] = 'rand';

	return $args;
} );