I have information on a possible Nintendo Direct happening between January 3rd and 15th.

>Super Mario 3D World DX gets announced
>Daisy, Toadette, Wario & Waluigi will be playable characters
>Yoshi will appear too but as a power-up

>Mario Sports MegaMix
>The old underrated Wii game gets a sequel for Switch
>All the sports from Wii (Dodgeball, Ice Hockey, Volleyball and basketball are returning)
> 2 new sports added. They are currently unknown
>Non-Mario characters like Ninja, Black Mage, White Mage and Cactuar are removed
>New Mario characters like Geno, King Boo, E. Gadd and Toadette are added
>Every character gets at least 1 skin/alt (I've heard of Dark E.Gadd, King Boo Luigi's Mansion, Mr. L & Captain Toad)

>Super Mario Party 2
>Reuses assets from Super Mario Party
>Game remade to be compatible with Nintendo Switch Lite
>More boards

>Mario & Sonic At The Tokyo 2020 Olympics DLC Season 1
>New events added (including dream events). Idk how many, my source was very vague on that.
>New guest characters (I heard Infinite The Jackal, Metal Mario & Pauline)

>I've heard of a new Mario Sports game (although this could be Mario Sports MegaMix) and new 2D/3D Mario game named "Project Mario Universe"

Pokémon:
>Pokémon will get a new mobile game. Title unknown
>Pokémon Home Service introduced
>More info on Pokémon Sleep
>Pokémon SwSh gets a small update, nothing special. It adds a little bit more Pokémon that were in the code through events

Super Smash Bros Ultimate:
>Fighter Pass 5 will be Phoenix Wright
>Other fighters my source heard of but is currently unsure about
>These fighters being Shantae, Crash, Waluigi, Bomberman & Isaac
>There seem to be a fanservice Assist Trophy promotion

Kirby:
>A new Kirby game reusing Star Allies engine

Sonic:
>A new Sonic Project is in the works, possibly coming 2021

Animal Crossing:
>Animal Crossing: New Horizons getting a new trailer.

Others:
>New Tomodachi Life game for Switch
>Small Mario Maker 2 update with new course elements (Power-ups added: Penguin Suit & P-Balloon + more enemies)
>New Wario game (not sure if WarioWare or Wario Land)

That's all I got.