"He is not just anybody."
Translation:Han är inte vem som helst.
Why is it incorrect to use 'bara' in the sentence? 'han är inte bara vem som helst'
Would anybody's be vems som helst? If so, should the difference be audible from vem som helst?
Doesn't "Någon" mean both "someone" and "anyone"? Could I use it here? Or am I wrong about this?
någon means 'someone' in some contexts and 'anyone' in others. Here, we're translating not just anyone and that is inte vem som helst in Swedish. Also as _JesseKat said, I recommend reading the post I linked to. I've forgotten what I wrote there, but hopefully it was something useful :)
I believe "Någon" can mean either and "Vem som helst" is a bit more specific [to anyone], and no, it can't be used here. I would read Arnauti's post in the comment currently at the top. I'd also recommend waiting for a native to check me.