I just took a look at this AddonStub and I'll be honest here. It is absolutely useless and pretty much the same as LibStub that we are trying to get rid of for that reason. Not sure why you would try to push this now?
Everything it is trying to do is handled by the game itself. There is no need to try avoiding loading duplicate addon names or check their addon version, since the game itself does exactly that. On the contrary, it is even slowing down the loading for no real reason, because it iterates over the whole addon list every time an addon is loaded, making it likely much slower than what the game itself does internally to handle multiple instances of the same addon in nested folders.
