There are two MIDI keyboards that i am aware of that can use the Tonnetz layout.
The Lumatone which you can define whatever key arrangement you’d like. ( thread )
The Akuto Studio AKT-0.1 which is currently being finish as a Kickstarter project. ( thread )
ADDED ( June 2024 ) : The Akuto keyboard is about to enter regular sales now.
If you aware of others let us know.
Don’t post other arrangements or something-like-it posts here. Tonnetz only. There is a very nice Alternative Keyboard thread, that needs those posts.