The "Mid 2 Points Snap" tool is found in the main part of the "Modes" Menu. It can also be found by itself in a "Custom" toolbar.
You can go to the "Commands" page of the "Customize" dialog and drag the tool out from the "Modes" category to a Menu/Toolbar of your choosing.
Designer, Deluxe, (Professional, Expert, Basic), Platinum
Windows 10 Pro (1803), 64-bit