It's... possible. But on the real steel, and likely the airsoft version as well, the selector switch is on the stock, unlike the Beretta and Glock auto pistols where the selector is on the frame/slide of the gun itself.
I'd imagine it would take replicating the extension piece that fits into the gun, making a copy of that part, and then glueing it in place. Kind of a crappy permanent mod for a gun that will cost you a couple hundred bucks. And if you mess it up, you're going to be out of luck with getting it fixed.
But, that's your money.
If you really want an auto pistol without a stock, look into the G18's. You'll also want to add a metal slide for durability.
Rook
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