When Admiral Picard is talking to Renée Picard in the hallway, a few Easter eggs from previous series are shown. First, on a stand next to where Picard is standing, is a model of the Nomad MK-15c space probe, launched from Earth in 2002, with a prototype artificial intelligence and Earth's first interstellar probe designed to seek out intelligent life. At some point it crashed into an alien probe called Tan Ru in deep space and the two units merged into an unstable sentient artificial intelligence. The probe was eventually encountered in 2267 by the U.S.S. Enterprise NCC-1701 in The Changeling (1967).
Second is the NASA space shuttle OV-165. While this is the first time any information is given about it the shuttle first appeared in the opening credits for Star Trek: Enterprise (2001). The number follows the registry system used by NASA from 1981 to 2011 for missions of the space shuttle program. The space shuttle Challenger had the registry OV-099 and the Enterprise was OV-101.
Second is the NASA space shuttle OV-165. While this is the first time any information is given about it the shuttle first appeared in the opening credits for Star Trek: Enterprise (2001). The number follows the registry system used by NASA from 1981 to 2011 for missions of the space shuttle program. The space shuttle Challenger had the registry OV-099 and the Enterprise was OV-101.
Picard lures Renee back to the gala by saying that Dr. Jemison is making a toast. This is likely a reference to legendary astronaut Dr. Mae C. Jemison, who had a cameo as Lieutenant Palmer in Second Chances (1993).
Including the "Previously On" recap and end credits, Two of One runs only 38 minutes. Apart from the Star Trek: Short Treks (2018) line of mini-movies, this makes it the shortest installment of a live-action Star Trek series.
Dr Ramirez's clinic is called "Las Mariposas" as seen on the clinic computer screensaver when she exits Picard's room. Mariposa is the Spanish word for butterfly. The butterfly effect postulates that a small effect can have very large downstream results, a caution for those who time travel.
Agnes performs a rendition of "Shadows of the Night" by Pat Benatar. This continues a long-held franchise tradition that people in the 24th century (and beyond) have a bit of a fixation with 20th century popular culture.