It's your responsibility to abide by payment provider rules when enabling a payment processor. Having your payments go through itch.io does not give you any special permissions. If we get a notification from a processor about content hosted on our platform then we will have to comply with their request.
That said, the payment processor terms for video games with adult themes is vague and a gray area. We can't really offer you any specific guidance about them related to whatever content you're selling. In our experience, mature video game content has not triggered any issues. But we can't make any guarantees about it, since it's not really our decision to make.
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