Faerun is a continent in the Forgotten Realms campaign setting. I think that, in essence, a campaign setting is like a universe. So the happenings in Eberron are completely separate from the happenings in Forgotten Realms.

So your concern that you'll be leaving one setting behind for another is founded, but my point was that, if the "they" you were referring to were the characters of Forgotten Realms, then they're not in Eberron. They're in Forgotten Realms.

What is it they say about silence being golden?