I just did, prior to my comment above. See attached video. That's the project demo of the first person battle plugin out of the box. I simply copy pasted the battle core and utils plugin into it.
If you're starting from a new project folder, then modify the x/y parameters of the actor sprites as well, as the default values are meant for a 1920x1080 resolution. The sample assets that comes with the project folder are 1920x1080 as well. Perhaps the reason you're not seeing them is because a new MZ project starts with 816x624 resolution, so the images are way off the screen.
























































