First of all, you can't avoid Turkish tax. Any
offshore company you form will be legally required to pay tax in Turkey, because it will be resident in Turkey.
In theory, you could form an EU company, open a bank or
EMI account for it, and process PayPal via this subsidiary. The problem is if PayPal decides to look very closely at your company and wants to see proof that the company has office and operations in EU, is paying VAT, and so on. Then having an empty shell corporation in EU won't be enough anymore.
Best is if you can set up an actual office in EU, or other jurisdiction supported by PayPal. Very expensive for a small business, though.
How much revenue are you losing out by not having PayPal? Is that revenue greater or less than the costs of setting up an offshore structure to accept PayPal? Depending on what digital products you sell, PayPal may or may not be as important as you think.
Have you considered other payment methods? Look at where your customers are from and see what other payment methods are popular there.