Anyone is aware of alternative for @@REMSERVER global variable?
There are no alternatives. All you see on that page is dead functionality, and earlier this afternoon I submitted feedback on that topic that should wipe out that text and say that the function always returns NULL.
What more precisely do you have in mind? This function relates to functionality that retains to remote servers, a functionality that has been discontinued. Since there cannot be any remote server, the function always return NULL.