This guide contains all the commands on the Admin System:
https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=213591107

And here a list of all the commands cvars types sv, cl, mp, sb, nb, etc. Some commands are visible in the console and others are not because they are launcher, that is, they are only executed by means of an autoexec file or launch options.

L4D2 Cvars list

You can create a file called "cvars.txt" and place it in the following directory:
C:\Program Files (x86)\Steam\SteamApps\common\left 4 dead 2\left4dead2\ems\admin system

This file will automatically execute all Cvars upon loading each map. Keep in mind each Cvar will need to be on its own line within the file.

Here's an example of how you can enter the Cvars:

Also through the command you can change when you are in a game:

Thanks so much