As part of Paramount+'s 55th anniversary Star Trek Day festivities, a new trailer for Star Trek: Picard was unveiled. In addition to announcing the release window for Season 2, the trailer provided the most extensive look at the upcoming season to date, including its time-traveling stakes as the omnipotent Q tampers with galactic history. With Jean-Luc Picard leading his friends back to the 21st century to restore the timeline before the temporal changes to reality become permanent, it appears that this particular mission may involve Picard and Seven of Nine teaming up with their dreaded enemy, the Borg Collective.
As Picard and his crew scour Earth of the 21st century for the source of the temporal anomaly that rewrote reality in their own timeline, they discover what appears to be the Borg Queen in captivity. The Borg Collective previously attempted to change history themselves in Star Trek: First Contact, traveling back to the 21st century to subjugate humanity before the creation of Starfleet. Whether or not Q's tampering takes place around this time period is unknown, but the Borg appearing on Earth in the 21st century is not unprecedented.
If Picard and Seven are set to free the Borg Queen as part of a larger plan to undo the damage Q has caused to the space-time continuum, this means they will not only have to help their most hated enemy, but ensure a timeline where the worst traumas they have each endured in their entire lives comes to pass at the hands of the Borg. Picard had been assimilated by the Borg during Star Trek: The Next Generation and turned into a deadly weapon against Starfleet, haunted by the experience. Similarly, Seven of Nine was assimilated by the Borg as a child, regaining her humanity over the course of Star Trek: Voyager.
The inclusion of the Borg and their role in Picard Season 2 also marks the return of the Borg Collective since its destruction in Voyager's series finale, with the Admiral Kathryn Janeway from an alternate future infecting the Queen and Collective with a lethal virus. There is the distinct possibility that working with the Borg Collective in the past could change the techno-organic civilization's future fate, potentially signaling a return of the Borg in Starfleet's relative present, especially if the captive Borg Queen learns what becomes of herself centuries into the future. The fate of Starfleet is very much interlinked with that of the Borg Collective now and, in order for Starfleet to be restored and survive, the Borg may experience its own revival as a direct consequence.
Q's temporal interference has transformed the Starfleet that Picard dedicated his life towards serving into a totalitarian regime. Somehow, these drastic changes are linked to the Borg Collective on Earth in the 21st century, with Picard and Seven of Nine forced to confront their greatest trauma personified to save the day. The Borg themselves have been conspicuously absent from the Star Trek mythos for some time, though their legacy loomed heavily throughout Star Trek: Picard Season 1. And with Picard taking things back to the past, it's clear that Jean-Luc and Seven still have unfinished business with the Collective all thanks to Q and his continuing trial of humanity.
You can see the Borg finally make their return when Star Trek: Picard Season 2 premieres in February 2022.