No not all masdevallia orchids are fragrant, however there are quite a few that are so I’ll mention the ones in my collection.
M Strobellii smells fruity like vanilla. M Meijiana smells spicy. M Glandulosa smells spicy. M datura very sweet smelling. M Caudata another sweet smell and lets not forget M caesia reminds me of rotting meat. There are too many to mention but I’m sure a good seller could advice better prior to purchase.