PayPal is still the only payment method accepted.
Swish is very local to just a very few countries and have therefore not been considered. We are also unsure of how well those payments can get automated, and the policies around them.
If we add another payment method, it's likely to be an international alternative. But most alternatives we have seen requires bank accounts in foreign countries which is a huge drawback.
If your credit/debit card doesn't work with PayPal, I am sure that your bank and or PayPal can solve that. Many banks doesn't allow websites to charge the cards for example. This can in some cases be toggled in the internet bank.
