I'd suggest not using a midi keyboard, but instead, using any keyboard which is capable of running QMK firmware.
This has the advantage that it can work in any application and doesn't rely on configuring your operating system/software for non-standard input devices (from the perspective of using it for keyboard shortcuts at least).
You could use the plank keyboard as a large num-pad, programming F-Keys 13..24, as well as other available keys.
For example, you could bind each key to a Hyper-[A-Z] combination, assuming you're not already using the Hyper modifier elsewhere.
See qmk/keyboards for a full list of supported keyboards.