i have a pf9 and i would look stupid trying to pocket carry it-too big. I'm average height/weight and don't see how anyone can pocket carry a 9mm subcompact, the Sig p238 or even a snubnose revolver. the only thing that I know of that doesn't print in the pants pocket is an LCP/DB380/P3at or a NAA mini revolver. Everything else is just too heavy and you'll likely feel awkward and print like a mug or maybe my skinny jeans shouldn't be worn when I pocket carry! ;-)
Yes a lot of the 9mm subcompacts are very large for a pocket. Can't comment on the Sig P238, but I would probably opt for IWB carry for that as well. In contrast I do pocket carry a Smith J-Frame snub quite often. No I do not wear skinny jeans and the secret is get this....a good belt. Yep folks it has been mentioned on INGO time and time again. Carrying a gun will require a good belt. Otherwise your pants flop and sag.
Don't get too concerned about the gun printing. A good pocket holster will break up the outline and it will basically look like a wallet, smart phone, keys, knife, flashlight, box of tissues or anything else a person might carry. Biggest problem I see with tight pants is that they reduce accessibility to the gun.
For what it is worth the mini .380s (LCP/DB380/P3at) are going to be the smallest and lightest to carry in a pocket. But that small size comes at a price.