So here's the thing:
He'll only give you the sword if you'll playing a linked file (aka, you've already beaten Ages and used the password from there to start a Seasons file). If it's a brand new file, then you can't get it until you beat Seasons, then linked an Ages file, then used the secret from there in Seasons.
Short answer: You can't get it without Ages. As for getting the password without doing all that stuff, I don't know. I've never really messed with that stuff, so you'd have to see if there's another thread here or on GameFAQs.