Darth Vader could encounter advanced droids that have developed personalities and even some form of Force - like abilities in this future. These droids might be a new challenge for him as they are not like the droids he is used to dealing with in his own time. He may also meet future versions of his former allies or enemies, who have been reincarnated or cloned in some strange new way, with different personalities but still with a connection to their past selves.
In the 'naruto is like darth vader fanfiction', their journey of self - discovery could be seen as similar. Naruto has to constantly figure out his place in the ninja world and how to control his power. Darth Vader is on a journey of self - discovery too, as he grapples with his identity as Anakin Skywalker and his role as Darth Vader. They also have a sense of isolation in some ways. Naruto often feels alone in his struggles, and Darth Vader is isolated in his dark armor, cut off from his former self and many human connections.
For the most part, the Vader comics are canon. They contribute to the broader narrative and lore of Star Wars and are recognized as part of the official storyline.