Direct will include the following announcements, in no particular order. I'll be first explaining Mario stuff, since Nintendo wanted to celebrate a belated Mar10 day.
>Paper Mario: The Cinemaster Experience
This is the return to form that the other folks have rumored.
Mario will have to explore the world of movies to stop the mysterious Cinemaster from trapping Princess Peach in his personal movie for eternity. Partners, unique NPCs, and the badge system is returning, but there will be a few twists to the battle system that I'll leave unspoiled for you guys.
>Luigi's Mansion 3: Gloom Service DLC
It's a post-game scenario with a few extra floors and a couple of new bosses, one of which is a guest character from Fire Emblem. Will not spoil who.
>Super Mario 3D World Deluxe
Will include the green Sprixie Princess as a playable character after you rescue her in the first world.
Will include levels from Odyssey.
Speaking of which...
>Super Mario Odyssey: Globetrotter DLC
Includes 2 new worlds: The Spooky Kingdom and the Sublevel Kingdom. The area in the Spooky Kingdom is named Catacreek, a small valley with parallels to the River Styx. The residents are these pumpkin-like things that I don't even know how to describe.
The Sublevel Kingdom is this huge underground area with these rock-like golem people called the Crogs. The area is called Crystalline Clearing. Two new costumes are also shown, which are Vampire Hunter and Miner.
Release dates for these three titles are Summer 2020, May 2020, and Fall 2020 respectively.
Next, we are shown a bunch of other ports, including Pikmin 3: Re-Plucked, a spotlight on Wonderful 101 (even though that's already been announced, but whatever) and even a port of Nintendo Land. Never thought they'd actually do that.
Next up, Xenoblade Chronicles Definitive Edition. The date is the same as the leaked Korean ratings board. Shows off some gameplay.
That's all I saw, but there's more. It's around 45 min and I only saw about 25.