Yeah it’s not overly difficult in mechanical terms, it’s just a matter of practicality. Energy cost, weight/size of the motor, battery weight, noise of the motor, complexity compared to something like a spud/BB gun, etc. I’m sure it would be less complicated than a pneumatic weapon like the PBD, but something similar that fulfills the same role of one-shot and powerful should be pretty easy. A spud gun or BB gun basically, but with an electric pump.
Pretty sure the Half-Life crossbow doesn’t even have enough strings on it, and the idea of firing a piece of red-hot rebar from a crossbow is pretty damn silly.I wouldn’t call it combat ready, and it doesn’t even auto load.