This is the wiki page for the console command:
The sleep command can be used to delay the execution of other console commands.
To run a console command with a desired delay, open the console and type
sleep 100; ball stop
Replace the 100 with desired delay in ms and the command after the semicolon can be any console command you want.
Usage in .cfg/.qk files Edit
Individual lines of commands in config and quicksettings files are run independently of each other. That means
will run both commands instantly. The sleep command won't delay anything because it has nothing behind it.
In order to get an action delayed, it has to be in the same line just like the console example.
sleep 100; ball stop; player velocity 0 0 0
This example when run, will instantly increase the gravity strength to -1000 and 100 ms later freeze the ball and stop the players momentum.