Hetman is the rank used by a Xepolite freighter captain.
In 2328, Foroe was the hetman of a freighter before he was detained by the Cardassian military near Bajor. (TLE - Terok Nor novel: Day of the Vipers)
In 2370, Drofo Awa was a hetman when Captain Benjamin Sisko and Gul Skrain Dukat discovered him smuggling weapons into the Demilitarized Zone. (DS9 episode: "The Maquis, Part II")