Hi,
We, Pinnacle Seven Technologies an official partners of Odoo with 7+ years of experience in doing end-to-end ERP implementation for all types of business process and we have worked from Odoo V6 to Odoo V11 on both Community and Enterprise Edition. We have work experience in customizing with shipping and payment gateway. Some out them are FedEx integration and iWallet bank payment gateway for one our clients. Kindly, get back to discuss in detail on the version that you are using currently and on the requirements in detail.