To install LiveAction:

1. Download the Unreal plugin from here. Please follow "Installation of Action and LiveAction" 

During the installation, select Action for Maya AND LiveAction as below, and select your Unreal Engine version. 

 After this, you will be asked to navigate to the location where your Unreal Engine is installed. Make sure that you select the correct version as per your selection of Unreal Engine. The three fields highlighted below should show identical Unreal Engine versions (4.17 in this example).


2. After installation, start Unreal and load LiveAction Window/Plugins/Animation