DestannZ

Here's some I use

sv_cheats 1                 // Enable cheats
god                         // No damage from zombies
noclip                      // Free-fly, pass through walls
player_sustainammo 1        // Infinite ammo without reloading
give <weapon_name>          // Spawn weapon, some are map specific though. Append _upgraded_zm to the weapon name for the packapunched version
r_fog 0                     // Disable map fog

I dont think you can turn 'death barriers' off via console. But..,

Press Win + R and paste:

%AppData%/Local/Plutonium/storage/t6/scripts/zm/

Within that folder create a new file called

_clientids.gsc

Open it with a text editor like notepad/notepad++ and paste in

init()
{
    level.player_out_of_playable_area_monitor = false;
}

When you load any of the zombies maps in T6, you will no longer be immediately killed when you have noclip on and go well outside normal map areas