Hey Mate,
Adding another owner allows others to edit, update and delete this flow. All owners can also access the run history and add or remove other owners.
>>What will happen if I leave the project and my user account is disabled and the Power Automate license has been removed from it? Will the flows stop working or will it continue to work since it shared with the service account?
If the shared flow still has an active owner, the flow will continue to run.
If the flow uses any active or embedded connections that belong to the user who has left the organization, those specific actions might fail but in your case as it is running user the service account that should not be problem.
But it is fails, to fix this, update the credentials with reference to https://docs.microsoft.com/en-us/power-automate/create-team-flows#modify-a-connection
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