Shutdown keyboard shortcut on MacBook Pro with Touchbar

Unfortunately it's not an option. There is an option for a sleep command, but there is nothing for Shut Down or Restart. Modifier/command keys on the sleep button don't work either.

Build custom keyboard shortcut to bring up shutdown dialogue (apple.stackexchange)

Touch ID button shuts down the computer (Apple Support) Another button on touch bar would be redundant.

Unlike with older Mac notebooks, holding down Touch ID on your 2016 MacBook Pro doesn't display a dialog with options to Sleep, Restart, or Shut Down. You can find these options in the Apple menu. If your MacBook Pro is unresponsive, you can hold down Touch ID for six seconds to force a shut down. Note that you'll lose any unsaved work if you do this.

Shutting down your 2016 MBP is not required unless not using for 36 hours (apple.stackexchange)

You can add a sleep or shutdown button to the touch bar in system preferences > keyboard > (set touchbar options - it's not called this but I can't recall the option name, it's toward the bottom of the screen) and then drag whichever optional button you desire to the touchbar

There is no shutdown button on Touch Bar (except hard poweroff), just a sleep button as customizable option, but we can add a QuickAction with Automator with a shutdown Script and assign a button on the Touchbar. I made a nice red "OFF" button. I wrote the detailed workflow and script to make it in https://discussions.apple.com/thread/251390862, taking the programming from https://discussions.apple.com/thread/8263239.