Hi,

This can be done with an Outlook rule, which is what I do. It's a very handy technique.

To create this rule, go into Outlook, then click on Rules...Manage Rules & Alerts...New Rule. Under the Start from a blank rule area, click Apply rule on messages I send, then click Next. You'll be presented with a list of conditions you can choose from but you can just leave them all blank since you said you wanted to affect all outgoing emails. After you click Next again, you'll be presented with a list of available actions, choose Defer delivery for a number of minutes. Click on a number of and provide a value of say, 1. Click Next, then Next again. Name your rule something meaningful, click Finish and you're all set!

Note that this rule will apply when using Outlook your local computer only, and not to any other method of accessing your email (including using Office 365, or on your phone).