You can add the call to actions the same way you do for the automated ones. If you do not know how to do that, please read this:
However, there are three things:
You cannot set a start time or a duration for the calls to action for live webinars.
You have to manually trigger them in the live console.
For hybrid events, you have to select for which type should the call to action appear, live or recorded or both. By default it is set to "Live"
The calls to action that you add to your events, will automatically appear in your "Live Console" for hybrid/live webinars. And you can just turn them on and off this way:
Please note: If you have multiple calls to action for the same location, only one will be displayed.