Theorized this in the main thread but I imagine the specific folders represent the EU specific announcements while stuff in WIP and Main Presentation is the worldwide stuff (since Nintendo usually segue into those segments individually when the Directs become separate).
I was told that the source behind this image is indeed legit. And from what I'm seeing nothing is outrageous.
Now: these could be just trailers for example, and Nintendo have trailers for every Nintendo Direct announcement afaik. There will still be new announcements and I think the games listed here are just those that have a release date and all.