Our regulators generally do not have protection for your VIN supply getting connected to the VOUT pin. There’s a lot more in play than just VOUT being greater than VIN. For instance, on the regulator you initially asked about, you can see there is a 10V rated capacitor on the output. If you connect some higher voltage to the output, you’re going to destroy that, regardless of if you manage to get VIN to be high, too.
There’s not an easy electrical way we know of for offering the kind of protection you are asking about. Perhaps you can do it mechanically, by using connectors that cannot be interchanged. If you can accept worse regulation, you could put a big diode on the output and not expose the regulator output directly, so the higher voltage could only be applied past the diode. That would waste power in the diode the whole time it’s in use, though, and the output voltage would vary depending on how much of a drop you get on the diode. Something like 1N4004 is not appropriate since it cannot handle enough current, and you would want a schottky diode with a lower forward voltage drop than a standard diode.