oh ok, the way it currently works is by parsing the filesystem and the addons_config.mk, the advantaqge of that is that you only need one file for all platforms, if we had visual studio projects per addon it would mean that people creating addons would need to create a vs project for them and if we add support for more build systems potentially a cmake file, a qbs, an xcode project.... which would make developing multiplatform addons really hard.
I think the current way where we parse the file system and then add exceptions in the addons_config.mk file if the filesystem parsing is not enough is a good compromise.
another option would be to have some kind of tool, it could be the same plugin, which generates those project files for each platform from parsing the filesystem and the addons_config.mk