Import orders and customers of eBay

We are one of the largest eBay shops in Austria and we are thinking of moving our shop-management to PrestaShop Manager and as we are intensively working with ebay, we would really appreciate not only the export of articles to ebay, but also the import of orders and customer.
Thus, the selling process can be done with one user interface.
We were using another tool before, which had this ebay API (but had other bugs and problems).

Thank you!
Stefan