Would be pretty pointless for me to make a video about as I don’t even install Launcher or Binary Engines into default folders, me making video with setup like would just cause more confusion.
Just figure out where the your stock UE4 is installed and navigate to it’s <Engine Version>/Plugins/Marketplace folder, is where substance plugin gets installed from Epic Launcher. You probably could just place plugin into similar place on custom/Gameworks engine folder before you generate project files but I haven’t tested . Otherwise you can just place the plugin on <your project>/Plugins -folder and then generate the project files like mentioned before.