Can my friends see me if I play games on a different server?

I have friends on Americas server in the battlenet app, if I play on Europe server, can people see me playing games? With and/or without the launcher being open.

I know when playing Overwatch for example on Europe server, my social tab is empty. So I think no one can see me from the Americas server but I don't know for sure.

Solution 1:

If you're playing on another regions server, you friends will not be able to see what game you are playing, however you will appear to be online in the launcher (and they will be able to message you).

So if you're playing on European servers, and your friends all play on US servers, they will just appear as online (or busy/away if that's what they set themselves too), and you will just appear as online to them too.