inb4 "the guy who isn't translating apocrypha"
Everything TM has published.
Everything Nasu has written.
The "core" Nasu works (name them).
The Nasuverse as a common setting and the works that follow its rules.
The stories & lore that you personally consider "serious", as opposed to "jokes/memes/etc".
Whatever fits your personal idea of what the Nasuverse is and how it works, fanon included.
Each TM work in its own right and in relation to its self-contained setting.
There is no canon, just an illusion of a consistent setting.