Planning on keeping it SE as it doesn’t technically conflict with anything established in the OT nor does it spoil the surprise (if there’s anybody on the player surprised by it now), nor does it detract from the film I don’t think. The crawl already establishes Vader is obsessed with finding young Skywalker, so having the emperor refer to him in that way I feel builds more tension in the film.
However, I am open to a discussion of possibly editing it to the original dialogue (except for “young Skywalker” instead of “Luke Skywalker”), and I know it’s possible as I’ve done it before, I just don’t have the edit I made anymore.