Currently, QuickBooks Self-Employed (QBSE) does not offer an option to permanently disable credit card payments for invoices once you're connected to online payments, Avath.
Yes, you're right. You'll need to turn off the Credit card payment option each time you create an invoice if you don't want to accept credit cards payments.

For additional guidance on managing invoices in QuickBooks Self-Employed (QBSE), you may refer to this guide article: Create invoices in QuickBooks Self-Employed
If you need further assistance or anything related to system capabilities, don't hesitate to reach out. We're always here to help and make sure QuickBooks works for you.