A number of the starships present at Frontier Day have engaged the Borg in the past: the USS Thunderchild (NCC-63549) was present for the Battle of Sector 001 in Star Trek: First Contact (1996) and several other ships including the USS Akira (NCC-62497), USS Clark (NCC-90206), USS Excelsior (NCC-42037), USS Luna (NCC-80101), USS Okuda (NCC-74107), USS Reliant (NCC-90200), USS Sutherland (NCC-91800) and the USS Venture (NCC-75306) were part of the armada that faced the Borg Singularity vessel in The Star Gazer (2022).
The USS Enterprise-E is briefly mentioned as being out of service and unusable, which Worf says is "not my fault." Showrunner Terry Matalas confirmed in an interview with ScreenRant that Worf succeeded Picard as the captain of the Enterprise, but intentionally wanted to keep the fate of the ship vague, saying, "I wanted to leave its exact fate open for someone to tell that story. It's more fun that way. Better left to the audience's imagination. What do you mean it wasn't his fault? Was it an accident? A mission gone wrong?! The possibilities are endless!"
A ship called USS Pulaski is briefly mentioned. The ship was named not after Doctor Katherine Pulaski from season 2 of Star Trek: The Next Generation (1987), but after Casimir Pulaski/Kazimierz Puwaski, a Polish officer in the 1770s who fought in the American Revolutionary War and saved the life of George Washington. Pulaski was an outstanding soldier and was called the father of the American cavalry. He is remembered as a hero who fought for independence and freedom in Poland and the United States, and is one of only eight people to be awarded honorary United States citizenship.