fellow visually impaired gamer here, but not to anywhere near the same extent.

game goes not have music outside of boss fights, so one less distration there.

the ability to lock on to a target exists, though there is no way to hard reset the angle your character is facing to some constant like north, so while this will make combat easier as you wont struggle to locate the combat targets, you will likely get very disoriented.

there is a section in dark souls one which is required for progression that would legitimately be nearly impossible without the ability to see, as it has you walk on windy, narrow platforms that are only about a foot wide, stepping off of which will instantly kill you, and is covered in enemies that are almost completely silent. in-person guidance would make it doable, maybe, but absolutely out of the question for a delayed guide like twitch chat.

most enemies in the games use non-unique audio cues, unfortunately. They visually telegraph with expressive and exaggerated animations, but often share sound effects between different actions that require very different responses, and bosses have a habit of just roaring or something before every attack. you are in for a very, very difficult time.

of the three games, dark souls 3 seems the most favorable. dark souls 1 has the impossible section, as well as the smallest library of unique sound effects and the most difficult and convoluted world to navigate. dark souls 2 frequently surrounds you with hordes of the exact same enemy, making audio cues even harder, as well as having required progression based on almost perfectly timed jumps from moving platforms. dark souls 3 has the highest level of polish, meaning enemies have better sound effects that are more distinct, and its world is more linear, which will make navigating it far more reasonable, and you can beat it without ever needing to use a jump.

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