Would the Insomniac Museums from Ratchet & Clank 2/3 count?

oh already added lol, shoulda smashed refresh!!!

Deadly Premonition has tons of action in a gallery

The Evil Within 2

Would the Nintendo Gallery in Wind Waker count for this?

Can't see Stanley Parable - one of my fave examples!

smt soul hackers and part-time ufo both come to mind as having levels take place in museums

outer wilds, shivering isles (maybe elder scrolls as a whole), fallout 3 (maybe fallout from 3 on as a whole), unreal life, arrest of a stone buddha, thirty flights of loving, zero zero (has a wax museum if that counts)...prob a lot more i cant remember rn

As well as Soul Hackers, the original Devil Summoner

Bubsy 3D: Bubsy Visits the James Turrell Retrospective

Pokemon has a storied history of this! Pokemon RGBY/FRLG/LGPE have a pretty simple one, Pokemon RSE/ORAS have an ocean science museum and a space museum. In ORAS the first gym is also done up to double as a paleontological museum as well! DPPT have a coal museum, BW and B2W2 have small art galleries, XY have a full fledged art museum, and SWSH… have a vault with historical artifacts, I guess? Some examples fit better than others but I don’t know I feel like Pokemon does this often to some degree and I’ve enjoyed the edutainment asides.

Bioshock Infinite's Clash in the Clouds DLC has a museum with unused Bioshock assets, concept art, and other stuff related to the development of the Bioshock titles.

Shivers by Sierra takes place in a museum.

I can recommend by Flesh of the Killer and Anthology of the Killer. The former takes place in a freeport that's been converted into an art museum. The latter uses a museum exhibit as the framework for the compilation and even features exhibits related to the series' development.