(covers information from several alternate timelines)
Procyon V was the fifth planet orbiting Procyon, located in the Andorian system.
In a possible future, the historic Battle of Procyon V was fought at this location in the 26th century, between the United Federation of Planets and the Sphere-Builders, wherein the forces of the Federation were successful in driving the Builders back into their transdimensional realm. (ENT: "Azati Prime")
Background information
A picture of a star chart supposedly used for I AM ERROR was tweeted by Ted Sullivan on 28 November 2017. According to this map, the star Andoria was also known as Procyon, or Alpha Canis Minoris. [1]
Apocrypha
In the game Star Trek Online, the Procyon system is not the Andorian system but rather a system directly adjacent to it, and Procyon V is said to be one of the first exoplanets visited by Andorian space explorers.