Calling external services "microservices" is fundamentally wrong. They are "services". All that will do is create a lot of confusion because you are utterly misusing terminology. You can't just decide to misuse terminology. That's like calling "red" "blue". You don't gain information by misusing well-defined terms, you create confusion and misinformation.
That said, your ideas on distributed systems is wrong. Any point in a workflow can and will fail. You need to account for all of this. You can successfully create an account on Stripe, and then when you bill that account, it could return an error. Or even worse, it can timeout, meaning you don't know whether or not a user was charged.
You have to take into consideration all of these failure situations. There is no atomicity in the way that you expect. Whenever things deviate off the happy path, you fail quickly and decisively so that everyone knows where they stand. That gives people the option to retry or call support.