Are you aware of any payment processor companies (such as Visa/MasterCard) that do not boycott adult content? Also, is there a list or reasonable way of checking if a company does?
Asking because my country has other card options and I would like to (if possible) switch to one that doesn't want to see me unemployed.
Great question!
Unfortunately, Mastercard and Visa process 76% of all credit card transactions, and they consider adult content "high risk" for their business. While independent payment processors can offer different terms, they ultimately have to abide by the credit card companies' rules if they want to process transactions at all. Remember that PayPal, Stripe, etc. sit on top of the existing infrastructure from credit card companies.
The higher risk for payment processors is not just due to lobbying from the NCOSE that aims to ban all porn from the Internet. The nature of selling adult content online is that it will always have an above-average number of chargebacks. Imagine, e.g., when someone calls their bank because they don't recognize a charge to "OnlyFans Inc." that their partner swears they didn't do.
Even crypto won't save us here. While it's relatively easy to put your money into crypto, getting your money out proves almost impossible due to the large amount of outright scams in that space, as documented on Web3 Is Going Great.
I would love to have an optimistic answer for you, but the truth is that it's all kinds of fucked, and possibly getting worse. As an adult content creator, your best bet is to hide behind the skirts of a large platform like Patreon, OnlyFans, or Itch.io to take the heat and handle transactions for you. But their protection only goes so far, and their rules for "acceptable" content are ever-changing.