Eltab
Lord of the Hidden Layer
In a similar vein, Gamma World can be used for a 'spoof' one-off adventure. I have no idea whatsoever if there would be enough player interest to turn a profit.There are some roleplayers who do rather Horror stuff than D&D. But Ravenloft is a thing for some of these.
This is a thing which other settings do not offer in this way.
(But unlike Strahd, GW needs two major rules sections - psionics ("mental mutations") and high-tech - that aren't ready yet.)