I think that aside of a good gameplay for a death stranding-like game, as i said, developing a good story is very important (atleast to me) in this kind of games, since it gives both context and a motivation for the player to progress, i though the sword being alive idea since that way one of the main mechanics of the game becomes a partner in your journey, though he is also an enemy!
Something cool i though about the story, if you use the idea i told you, is that the story could be about you and "your sword" being cursed but since he is technically your partner, you are collecting money to somehow break his curse.