function misha_hide_out_of_stock_option( $option ){
	return 'yes';
}

add_action( 'woocommerce_before_template_part', function( $template_name ) {
	if( 'single-product/related.php' !== $template_name ) {
		return;
	}
	add_filter( 'pre_option_woocommerce_hide_out_of_stock_items', 'misha_hide_out_of_stock_option' );
} );

add_action( 'woocommerce_after_template_part', function( $template_name ) {
	if( 'single-product/related.php' !== $template_name ) {
		return;
	}
	remove_filter( 'pre_option_woocommerce_hide_out_of_stock_items', 'misha_hide_out_of_stock_option' );
} );