What is the font used on Console.app in macOS Sierra?
The font used in the Console.app on macOS Sierra is the SFMono-Regular font.

This can be found in /Applications/Utilities/Console.app/Contents/Resources/Fonts

More versions can be found in Xcode8 directories for example here:

/Applications/Xcode.app/Contents/SharedFrameworks/DVTKit.framework/Versions/A/Resources/Fonts/