In terms of user experience IMO, what you’d want is something similar to how Apples “share wifi password” work but with extra features. You want to log in to x

In terms of user experience IMO, what you’d want is something similar to how Apples “share wifi password” work but with extra features. You want to log in to x, there’s a place to put the owners email or phone number, they get (if you are previously on some “accept list”) a notification that let’s them grant or deny access. You don’t get to see any password, you just get logged in. Ideally you’d also want them to be time limited and revocable.