Just from a quick browse through Framework's replacement parts, almost none of them specify which version they're designed for. So either they're all interchangeable with any chassis version, or the website has an enormous usability problem and can expect a lot of unhappy customers. (I don't own a Framework and I have no idea which of these is the case.)
The newly announced but not yet released 16" model has some also not yet released GPU modules that require a 16" chassis, but all iterations of the 13" chassis are interchangable and compatible and I believe the 13" parts work in the 16" too
