Not fanfic
But I had an idea for a Trek RPG based around the idea that Dr. Lenora Khan is able to stablize the Barzan Wormhole, thereby providing Wormhole access to the Delta Quadrant.
Now Starfleet would begin building a major staging area on the DQ side of that wormhole, and I think Starbase Delta is just crying to be that station
She would be home to the Delta Quadrant Expeditionary Force. A fleet of ships checking up on what Voyager learned and reported back to Starfleet.
You assess the effects of Voyager on the DQ and the current state of the BORG.