Fuck, this is harder for me to decide than I thought.
BotW is pretty good, and Cuphead was a goddamn delight. The problem is that a lot of those games are games that fall under the category of "games I WANT to play, but haven't because I'm not made of money." Neir and Resident Evil 7 fall under those categories. I bought Horizon on the Black Friday Sale, but I haven't gotten a chance to play it yet. Also people have also brought up Divinity 2 and PUBG, two games I ALSO want to play. Hell, there are games that havne't been mentioned in this thread that I'd also want to mention, like Yakuza 0 (Haven't played), Mario Odyssey (Played) and Halo Wars 2 (Haven't played and probably gonna be the last Halo game to grab my attention baring 343 getting its shit together,) Oh, and I guess Nioh. I mean, It doesn't look bad, but it does kinda scream "Dark Souls clone" and I've already got a good Dark Souls clone, it's called Bloodborne.
But I can't vote for games I haven't played. So I'll have to go for a game that utterly blew my freaking mind as well as a game that brought back comforting memories of how earlier entries in the series helped me get through college when I played them for the first time.
Persona 5.
Though I want to give honorable mentions to Hand of Fate 2 and Endless Space 2 two freaking great under the radar games.