You cant launch it and play online but you can launch it through lan via a bat file.
FOR T6 OFFLINE LAN
First time users that never run Plutonium.exe. You still require some type of temporary internet to download the plutonium files from the launcher in order this to work. after that you should be good to go for now on until the next update. Also you can transfer the %localappdata%\Plutonium from another computer but be warn that your players system config files, account token and possible IW5 stats will be copied over as well.
Hit your windows key and R key at the same time
copy and paste the following line on the run window and hit enter or ok.
%localappdata%\Plutonium
Now depending on your file explorer options. you may have to uncheck hide extensions for known file types. you should see bin, games, launcher, storage, config.json, info.json
Right click below info.json. and go to New > Text document
Now rename the full New Text Document.txt to something like T6MP-LAN.bat
Right click on T6MP-LAN.bat and edit.
Add the follow lines on notepad. You may have to edit couple lines after t6mp.
Echo off
.\bin\plutonium-bootstrapper-win32.exe t6mp "C:\Program Files (x86)\Steam\steamapps\common\Call of Duty Black Ops II" +name "John Smith" -lan
Hit file and save and run T6MP-LAN.bat. you may have to create a shortcut to desktop for future use.