Hi Tulsa. I'm not sure what you mean by metal studs. Could be you are referring to Rivets which, for those who use them are placed at what are thought by the maker to be stress points. You could also be referring to snaps which are used in some retention strap applications. In either case most experienced makers make sure none of the metal on either application is exposed on the INSIDE of the sheath. As an example, all my sheaths are fully lined and the snap, Sam Browne Stud, or whatever is at minimum between the lining and the body of the sheath and no metal can or will come in contact with the knife. In the case of rivets at stress points (which I will never use), they generally go through the middle of the welt and therefore cannot come into contact with the blade.
You referred in your original post to many posted examples and I cannot think of any I've see here or on other forums, made by experienced makers that fit that description, Cheap Chinese factory type stuff maybe yes, but custom made.....I doubt you wil see it.
Best Regards,
Paul