I'm trying to implement Stripe payment in my Flutter mobile app, but I need to finalize the payment on server side.
Does anyone know how I can do this with also 3D secure/sca? I am able to show 3D secure/sca page only finalising payments on client side. Checking online documentation, I have found this: https://stripe.com/docs/payments/accept-a-payment-synchronously, but stripe packages (I have tried with stripe sdk and stripe_flutter) don't provide stripe.handlecar action.
To answer your headline question: You cannot. If you could, the whole security feature would be pointless. You need client side authentication.
PSD2/3D Secure/2-factor-authentication or any other mechanism relies on the bank to tell the client what to do to authenticate. They might reroute you to a different site, owned by the bank, they might ask you for a PIN or one-time-code, or anything else they deem suitable. They will interact with the user, that is the only point of all this.
The method that will handle it is called confirmPaymentIntent (might vary a little depending on which package you use). It will need to be called client side with a payment intent for the payment. It will then show a testing screen for the test card numbers stripe provides.
