Everything from the Old Republic is Canon. Everything from the High Republic is Canon. Everything from both continuities in the prequel era is canon. The Clone Wars Multi-media project has been combined with the show and surrounding media from Canon. In the early Imperial era (when this series takes place) both continuities exist. If anything is referenced onward, which won't probably happen, I'm sorry, but Legends takes the cake pretty easily (OG Thrawn Trilogy over the sequels on any given day). THAT BEING SAID, in crossover events the other sides continuity preferences will be the only ones mentioned, as to save it all. Anyway, most of SWTOR is referenced in Canon books enough to be almost Canon.
