The XL leg holster - despite being suitable for use with shotguns, smgs, and rifles, and requiring a minimum volume higher than most pistols without heavy modification - requires Pistol 3 to craft.
It should probably require Marksmanship 3.
Im under the impression that since the regular holster requires pistol that this one does too by extension.
I think it would require marksman 4 or 5 if youre going to use a general skill like marksman. Thats nothing more than using a slingshot.
I’d take the Rifle Skill. Most Shotguns have at least a similar build as a normal Rifle (unless they have a rotary magazine or something like this), so that would work too. Smg’s might be a bit trickier, considering that they are more like something between a pistol and a rifle (form & size only of course).
I seem to remember that there are SMG holsters in the real world - bigger than a pistol holster, can take very big pistols, but smaller than a holster for rifles/shotguns. Maybe something would be a good idea, then you could put smaller smgs into the smg holster and bigger smgs in the XL holster with shotguns and rifles.
Time to implement a: "needs either skill a or skill b’ system