To solve a problem like this, it’s good to make a small sample to reproduce symptoms. I suggest making a small empty project that has a different project name, module name, and plugin name, and the names of its derived elements are different from each other. And try to rename that (with core-redirect?) It will make it faster to test and learn.
And, sometimes I experience confusion about those, too, as same as your situation. (This means the information that I gave you could be wrong 
) You are not alone 
I wish you good luck.