Library/Application Support/Godot/app_userdata/PNGTuberPlus
So to get to your Library, you go on your desktop, click on GO on the top of your screen hold down “Option” the Library folder will pop in the list, click to open window, then you just follow the the above folder links. You are going to have a lot of folders so take your time to look to find the name of the folders.
Once you get to the PNGTuberPlus folder you just have to click and drag your images in that folder.
The only issue I have right now is my mac is not allowing the App to use my microphone for it, so If someone knows how to give the app permission that be helpful as well (I did check the permissions in security but PNGTuber+ isn't even showing up on the list.)