Undo Send
Set how long a sent email waits before it actually leaves.
The undo send window is the pause between selecting Send and an email actually leaving, during which anyone can pull it back.

Go to Settings > Undo Send.
Choose a delay: 5, 7, 10, 15 or 30 seconds.
Choosing Off removes the pause, and mail then leaves the moment it is sent, with nothing to undo.
This applies to every teammate; there's no per-person setting.