I think not having a load will give a challenge as @anon36505037 mentioned, since it is needed for dead-device detection and calibration. If just using it as a remote switch, why not use something from this thread:
Or one of these:
(maybe this but Im not sure about compatibility, though price looks good)
Seems like overkill if you just want a remote zwave switch to associate with another controller… You can always connect the switches on the remote with normal-looking wall switches with a small modification. Even a small Xiaomi button from China would work (though would need CoRE linking rather than pure ZWave…)