Switch:
Crash 2 and 3
Donkey Kong Country Tropical Freeze
Xenoblade 2 and Torna Country
Doom
Wolfenstein 2
Skyrim + Dawnguard and Dragornborn DLC

Fire Emblem Warriors
SNES online Yoshi's Island

Smash- beat world of light and unlocked all characters and pre-dlc spirits

PC:
Battlefield 4
Halo Reach
Final Fantasy 6
Star Wars Dark Forces
Batman Arkham Knight
Far Cry 3

Wii:

The Conduit
Conduit 2
Medal of Honor Heroes 2
Call of Duty World at War
Modern Warfare Reflex
Modern Warfare 3
Red Steel 2
Sonic Colors

Super Mario Galaxy

Super Mario Galaxy 2

3DS:

Pokemon Ultra-Sun

Star Fox 64 3D

Eshop:
Super Mario Bros 3
Super Mario Land 2
Super Mario World
Legend of Zelda

Wii U
eshop:
Super Mario 64 100%

N64:

Star Wars Rogue Squadron

- Hollow Knight
- SSBU (World of Light)
- Gris
- New Super Mario Bros U DX
- Okami HD
- Yoshi's Crafted World
- Cadenc of Hyrule
- Mario Maker 2 (100 solo lvls)
- Astral Chain
- Zelda Link's Awakening
- Luigi's Mansion
- Ori and the blind forest
- Dead Cells

Final Update. I'm sure this is the most games I've ever finished in a year by far and managed to cross of some games that have been stuck in my backlog for a very very long time and finish them for the first time. (Super Mario Galaxy, GTA Vice City, Resident Evil 4, Fallout 3, Borderlands)

Super Mario Galaxy
Spiderman (PS4)
Crash Team Racing Nitro Fueled
Borderlands GOTY
Borderlands Presequel
Rise of the Tomb Raider
Farcry 4
Team Sonic Racing
Farcry Primal
Persona 5 Dancing in Starlight
Dangan Ronpa
Dangan Ronpa 2
Slay the Spire
Resident Evil 4
Fallout 3 GOTY
The Outer Worlds
Grid 2
Ratchet & Clank Crack In Time
God of War
Horizon Zero Dawn
GTA Vice City
Spyro 3 (PS4)
Shadow of the Tomb Raider
Batman Arkham Origins

I know this is a bit late (work has been wayyyy too frantic the first month+ of this year!), but I don't think I am (or at least I hope I'm not!) falling foul of the necrobumping rule. For 2019, I set a goal to see if I could average one game per week (for no particular reason), and, at least by my standards, I did just that. Overall, 2019 was another great year for gaming for me.