It would depend on context and tone of voice. It would be possible to say 'Hey you' in an inviting way (to someone you know very well - 'Hey you - great to see you again!'). But more often than not 'Hey you' sounds aggressive (and may be regarded as impolite: 'Hey you - can't you read? Get off my land.'is it different from just "hey"? more inviting?
is it different from just "hey"? more inviting?
I'm asking about occasions when an email starts with "hey, you" or people greet somebody they know saying "hey, you", so it's definitely not offensive or aggressive or to get attention
What I'm trying to understand, is it always (a bit) inviting (especially in writing) or depending of your tone it can be neutral?
On the other hand, if you want just to be neutral, why would you say "hey, you" instead of just "hey"?
Also, is it only OK to say this to the opposite sex or it doesn't matter?