As others noted, it is pretty simple to add the command(s) yourself into plugins and recompile them. There are numerous guides/threads on these forums for doing so.
If you are looking for an option that allows using a cfg to add chat commands to execute client/server cmds, return messages, create menus, etc., I have one. PM me for details.
Originally Posted by 8guawong
why do you need to do this?
Sometimes other plugins dont register the cmds and the user may not want to recompile (or want to learn how). Additionally, some console commands are not SM commands from a plugin but can be executed on a client by the server.