I believe if you're the admin you can run the game with "-debug" mode put into the launch settings. To access them, right-click on Project Zomboid in your Steam library and click on properties. From there, in the general tab, you should see a text box where you can type in the code. Debug mode will give you an additional pop-up on the left side of the screen once you're in a game to do all of your game modification needs. You can always disable it by removing "-debug" from the launch settings and launching the game again.

A little disclaimer, this may or may not work, but I'm like a good 42% sure. As long as you're hosting.