How do I remap the Bixby functions in the button to something else?

[TabGuy]

Title says it all

 

[fredwardnelson]

First, head to Settings by swiping down the notification drawer and tapping the gear icon, or find the Settings app in your app drawer. Now go to Advanced features > Side key. You’ll see an option to customize the Press and hold function of the button. Simply choose the Power off menu option, and that’s it. Your sleep/wake key will now also offer the power off menu when you press and hold it.