Hi there. Have you tried adding this plugin to your projects “Plugin” directory? Like copying it from the engine installation directory.
Just a shot in the dark here to be honest, but might be worth a try, if not already done so.
I copied the plugin into the projects folder and tried to ship the game again, but this time I got another error which was related to the plugin again. I could resolve this with a quick google search and the solution was to delete the plugin from the engine folder.
So basically removing the Plugin from the engine directory and placing it into the project directory solved the problem.