i'm sorry, IMO, i cant use any irc client without these features and until these are added, i will use xchat

Your loss. You'll be using the programme that in reality you don't really like because you refuse to add a five line script, to the programme you apparently do like, that satisfies your nick completion problem.

Code:
on *:input:#: {
  if ($1 ison #) {
    echo $colour(own) -ta < $+ $me $+ > $1 $+ : $2-
    .raw privmsg $active $1 $+ : $2-
    halt
    return
  }
}
30 seconds work, though there's probably a better way to do it, if so, by almeans post it.