Honourable mentions from me go to Hellblade: Senua's Sacrifice and Super Mario Odyssey.
Hellblade is the single most emotionally powerful game I have ever played, a masterful study of trauma, resilience, and survival with a deeply human protagonist whose story absolutely captivated me. Doesn't hurt that it's also looks gorgeous and has excellent combat.
Super Mario Odyssey's sheer creativity is just incredible; there are ideas good enough to build a whole game around in almost every level. This one really had the misfortune of coming out in a year where BOTW dominated the conversation; had it come out in 2016 nor 2018 it would have been my game of the year by a mile.