From the introduction to the first episode:
The Legacy of War is a roleplaying campaign for use with the new Universe of Babylon 5 rules, which incorporate the Traveller rules into the Babylon 5 Universe. This campaign is intended for up to six starting characters. The story assumes the GM has a reasonable knowledge of the main television show and Crusade series.
The story begins shortly before the events of “A Call To Arms” and runs parallel with the established Crusade storyline and beyond. The premise is similar to Crusade in that the players will explore the galaxy looking for alien technology (and eventually a cure for the Drakh plague).
The 14 parts to this adventure series appear in Signs & Portents issues 63-76. All are written by Simon Beal.