Hey @tfarsund
If you trigger a flow from PowerApps, all the connections to the actions in the Flow will be used of the user that is triggering the flow from the PowerApp control.
To send all emails from one account only, you can setup a shared mailbox and provide all these users (the ones who have access to the app) as members of that Shared Mail box and in the flow, replace the send an email action with send an email from a shared mailbox action.
Hope this Helps!
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