Dark Souls is an example of a game that doesn’t work as a movie in its current form because of how it tells the story (it almost doesn’t)
It most certainly tells a story, the volumes of Vaatividya and lore videos can attest to that. There is lots of lore, tons of narrative, worldbuilding, etc. in this game. It just happens that it is not presented in the usual standard way. A game like
TLOU presents it's story via themed level design connected by movie-like cutscenes. It will be easier for a movie or tv director to copy that story just because it is already presented in a visual way. But it does not mean the story is not there for
Dark Souls. It is simply told in a less direct way.
The lore and story of Dark Souls could certainly be depicted in movies. It is not a hopeless task, it would require consultation with an expert like Vaati, but it can be done.
Flashbacks to the Sisters of Izalith, or Artorias and his Wolf, or Oolacile, can be intercut with the lead character traversing through the current lands, providing worldbuilding as well as cool visual and action setpieces.
The game has wonderful flow to it and I think it would make a good movie even just replicating the usual way through the game. The movie could start with the intro cutscene showing the various baddies and talking about the dark soul and all that. Then it starts in Undead Asylum, the camera panning across the floor, them replicating that opening shot in live action. The first action is a dead body hitting the ground of a dank jail cell with a cowering Chosen Undead in the corner - the lead character. He peers out into the light and looks up to see his savior. He investigates the body to find a key and uses it to escape his cell. Soon enough, he will come upon a dying Oscar who gives him his task (as well as the all-important Estus Flask). It would be very interesting to use the various characters in this game and have them show up at various points of the movie. Onion Knight in particular, I can easily see the movie having us walking through a forest and coming upon Sen's Fortress and meeting this guy outside and that being a scene in itself where you just hang out in this fantasy land with this quirky knight on some mystery quest. We can show the lead learning gestures as well by befriending NPC characters.
The real problem is, there seems to be so much lore in DS, you kind of will have to decide what to cut and what to keep. Probably focusing on Gwyn and his children and kingdom is a good idea. Then pick out a few of the better NPCs to interact with the Chosen Undead and elaborate on their stories. The Primordial Serpents, of course, will play a large role. The movie ending in the Kiln of the First Flame seems very appropriate and visually that would be a cool thing to see!
Feel like this is a movie I really would want to see! There is drama, tragedy, humor, everything in
Dark Souls. So much there that could be mined for a great fantasy movie. Or a trilogy even.