Who flows can email
Daily limits, unsubscribes and the sender name.
Emails show "your organization via xMap Flows" as the sender and replies go to the flow's owner. On the free plan a flow can write to your organization's people and addresses at your company's domains; paying organizations can write to anyone. There is a daily number of emails per organization.
An address that unsubscribed, bounced or reported spam gets nothing more from your organization.
The same rules hold for addresses a flow takes from its items (To set to a field such as {{contact_email}}): on the free plan an address outside your organization's domains is skipped and counted in the step.