This article helps us to understand the way to send emails without the user context. This could be applicable for applications, where consumers/users are non-licensed.
This could be achieved with the help of few set of actions on Power Automate flow. Here Microsoft graph end points are used to send emails on power automate, based on application permissions. The app permission needs to be enabled on Azure AD app.
Let us only look at the power automate configuration, instead of end-end business scenario. The following snapshot shows the actions.