Given you have standard plugins, this should work.
Put this somewhere in your EVENT_SAY (global_player.pl) or wherever you want to trigger this.
Code:
sub EVENT_SAY{
if($text=~/#gmzone visuals/i){
plugin::SendToInstance("public", "overthere", 1, 1836, 3098, -50, "GM_Zone3", 604800);
} # Send to Overthere for Weapons/Spells Preview
}