Well considering the Switch probably won't get most 2019 releases until 2021, I can't say I came across any gaming-wise. Some nice re-releases/ports/remakes this year, though.
For music, I guess some lesser known stuff that I've enjoyed from 2019 includes Blood Stain Child's "AMATERAS" album, Seraph In Travail's "Lest they Feed Upon Your Soul," and Mechina's "Telestrion." Midnight Odyssey also put out an extremely impressive 2019 release and if you're a fan of black metal I highly recommend a listen through his album, "Biolume Part 1- In Tartarean Chains."
Movies, I don't know. The only movie I saw from 2019 this year was Toy Story 4. And that's not a hidden gem, definitely all over the radar. It was good though, just kind of overly existential for a kid's movie.