John Byrne was part of some really interesting experiments during his time at marvel in the 1980s. He left Alpha Flight to trade books with the creative team of Hulk. He had a sideways issue of the FF. And, in these two annuals, he and Roger Stern told the same story from two different points of view. See how the covers reflect the same scene?
They do meet up, of course, in the middle–and have to figure out who is who…
Taking place right after The Beyonder “saved the day” during a battle between The Avengers, The Skrulls, and Nebula’s forces from Titan, Starfox was frustrated by not having a chance to finish things with Nebula. The team goes after her and gets involved in some intermural Skrull stuff (it’s great—you really should read it), with a huge consequence: All Skrulls find their genetic codes altered and lose their ability to shape shift.