Ori, Mario 3D World in Mario Maker 2(does this count?) and Hollow Knight.

Edit: Rayman Legends/Origins and Tropical Freeze as well.

Cuphead. Nailed the cartoon look.

Rayman, Trine and Ori would be near the top of my list.

But for me, although not technically most impressive by a long shot, its art style is something that enchanted me the most - Machinarium

Owlboy

Legend Of Mana

Tales of Eternia

Ducktails Remastered

The Last Night (not released yet)

Ori:

Trine :

Cuphead:

Tropical Freeeze : 

New Super Mario Bros Wii U.... nah just kidding.

Ori and Rayman Origins/Legends

Since no one has mentioned it yet, I'm gonna say Ori and the Blind Forest.

This a very tough question. Cuphead, Ori, and Trine are all great examples, but we could go on with more and more entries. I guess another one is Child of Light. There are several faults with the style, such as with the character models, but the decadent look of it is astonishing as well.

I forgot Gris.

Hollow Knight. Its both beautiful and atmospheric.

Other candidates for me are Rayman Legends, Owlboy, Trine and of course, Tetris.
Havent played Ori tho.