Hey,
If it is a plug-in then a simple way to have this load is to use maya's module system.
In your Documents/Maya/2020/ folder create a folder called Modules.
Now create a folder structure inside like this:
Leuchtkraft/plug-ins
Copy the python file and the subfolder into the plug-ins folder.
in the Documents/Maya/2020/modules folder create a text file called: Leuchtkraft.mod
In the text file paste this: + PLATFORM:win64 Leuchtkraft 1.0 ./Leuchtkraft
Restart Maya and if the Leuchtkraft
thing is setup as a proper maya plugin, it should show up in the plugin manager (not sure on what name it would show up but you could use the search thing to filter for Leuchtkraft
(I've attached a zip of the folder structure and .mod file based on the name:
Leuchtkraft)