Are you able to use the Alby extension in a browser? You can add multiple accounts to the extension and then switch fairly easily to login. Not quite as seamless as how Nostur has implemented it, but I use Alby with 2 different accounts that way and it works pretty easily.
Discussion
Great pointer. Thing is Alby requires a LN node to set up an account... but I simply copied over the same LNDHub URL and it created a 2nd account where I'll put a new nsec