I don't know to which country do you guys sell more but here in Brazil we have at least 4 payment gateways that allow filesharing sites. There are also a local payment method called "boleto" which is like an invoice that the client can pay on any bank and the money is delivered directly in your bank account. The payment gateways have fees around 10% and boleto has a fixed fee of +/- 2$.
However, you must have a bank account here to accept any of those methods and you must be a registered company to accept boleto. There are also some taxes to convert the money to USD.
Anyway, if someone needs some help with this send me a message.
Does anyone knows cielo? It's a credit card operator that process payments using visa and mastercard. They have a quite simple gateway solution: https://developercielo.github.io/Checkout-Cielo/english.html
They also have a webserver solution that allows you to process the payment without redirecting the visitor to their website.