Including many payment methods can help the user choose the one that fits them best, but can also be overwhelming and a pain to set up. So please try to use as few different payment gateways as possible. Our recommendation is either Stripe or adyen as they are the most flexible.
Stripe is one of the most well known payment gateways out there, but is also fairly expensive, but easy to set up. See here for pricing information and sign up here
Adyen is used by small and huge businesses alike, but you have to email their support team for account creation, which is easy to do, but takes longer to complete. adyen is fairly cheap, "only" charging 0.10$ per transaction plus payment method costs. Detailed pricing information can be found here and you may sign up here
https://www.payrexx.com/en/pricing/