Star Trek: 10 Things You Didn’t Know About Wolf 359
2. Multiverse Of Massacres
The many-worlds interpretation of quantum mechanics isn't just good for variations on cake and combadges. In Parallels, Worf's surprise party-hopping trip across the multiverse also included the worst of worlds, an Enterprise-D that hailed from a universe in which the Borg had destroyed the Federation.
That was one (very grim) way The Best of Both Worlds two-parter could have concluded. Beta canon has imagined other possibilities for the Battle of Wolf 359 itself. In the Shatnerverse novel Spectre, the mirror universe's 'Wolf 359' didn't involve the Borg at all. Instead, it was a fight between the Terran Empire and the Klingon-Cardassian Alliance lasting three days. Terran losses were Federation of Prime's multiplied by ten.
On a comparatively lighter note, if only for the fun of a crossover, IDW's 2012 eight-issue Star Trek: The Next Generation/Doctor Who: Assimilation² comic book mini-series also featured the Battle of Wolf 359 from its own multiversal Borg/Cybermen perspective.
At the end of the sixth, and into the seventh, issue, the Eleventh Doctor, Amy Pond, and Rory Williams take the TARDIS back in time to Wolf 359. Once there, aboard the Borg cube, Pond implores the Doctor to do something to prevent the thousands of deaths. The latter simply replies that the battle is "a fixed point in time [and] can't be changed".