Константин Тимошено

Решил! Сделал скрытое поле возле кнопок

<div class="button-submit" style="text-align:right;">
			<input type="text" name="custom_value" value="" hidden id="custom">
			<button type="submit"
			        name="add-to-cart"
			        value="<?php echo esc_attr( $product->get_id() ); ?>"
			        onclick="jQuery('#custom').val(555)"
			        class="button alt single_add_to_cart_button">Заказать еще</button>
			<button type="submit" name="add-to-cart"
			        value="<?php echo esc_attr( $product->get_id() ); ?>"
			        class="single_add_to_cart_button button alt">Оформить заказ</button>
		</div>

и в functions.php добавил action

add_filter( 'woocommerce_add_to_cart_redirect', 'stamp_skip_cart' );

function stamp_skip_cart( $redirect ) {

	$cart_items = WC()->cart->get_cart();

	foreach ($cart_items as $cart_item ) {
		if ($cart_item['tmpost_data']['custom_value'] == 555){
			return get_home_url();
		}
		else{
			return wc_get_checkout_url();

		}
	}
}

Помогли решить так

add_filter( 'woocommerce_get_price_html', 'product_price_free_zero_empty', 100, 2 );

function product_price_free_zero_empty( $price, $product ){
if ( '' === $product->get_price() || 0 == $product->get_price() ) {
    $price = '<span class="woocommerce-Price-amount amount">Цену уточняйте</span>';
}
return $price;
}