Stellar Blade from SHIFT UP Corporation has been rated Steam Deck Verified by Valve ahead of the release on June 11th.
Not exactly surprising, since when I checked out the demo previously I was really properly impressed with the performance of it. Although the defaults aren't the best, it does perform well. Valve noted in their checks that the first-time setup does require an internet connection and it might not default to external controllers, so you need to swap them in the Steam Deck UI. Apart from that, it seems it's good to go!

Direct Link
It goes to show that modern games can still be optimised for the lower-end devices.
About the game:
The future of humanity is balanced on the edge of a blade. Ravaged by strange, powerful creatures, Earth has been abandoned, and what is left of the decimated human race has fled to a Colony in outer space.
After travelling from the Colony, EVE arrives on the desolate remains of our planet with a clear-cut mission: to save humankind by reclaiming Earth from the Naytiba – the malevolent force that has devastated it.
But as EVE tackles the Naytiba one-by-one, piecing together the mysteries of the past in the ruins of human civilization, she realizes that her mission is far from straightforward. In fact, almost nothing is as it seems…
Can't wait to dive into this one fully. Although it's going to be a while for me, the sands of Arrakis keep calling my name.