Dumb question, which is the papist, the traditionalist supporting VatII?
Actually, a good question, and yes, as "shorthand," the supporter of Vatican II and (currently) Francis, would call himself a Papist.
But it occurred to me after I had posted yesterday, that the sedevacantist would respond that he, too, is a Papist -- he just doesn't think that John XXIII, Paul VI, etc. were real popes.
So, technically, they both can be called Papists. OTOH, a sedevacantist would not use the term too often, lest people think it implies loyalty to Francis. But he might use it if the context of his POV was clear.