All these are "neo-folk" (synthesizers and stuff that imagines what music that we have no surviving sources for would sound like. Contrary to popular belief, there is no surviving music or tunings from Viking Age music. We have no idea what it would have sounded like.)

An actual Scandinavian folk band would be something like Svanevit, just a few people only playing traditional instruments and songs. Their album, Rikedom och gåvor is an arrangement of traditional songs from Skåne for traditional strings and wood instruments.