Narn would have a militant revenge faction and a fatalistic faction.
I don't see either the Shadow or Vorlon having factions as they are their own mutual enemies.
The Vorlons do have two factions.
There is the one faction that Kosh Naranek belonged to, that want to protect and guide the younger races. Since this was the original goal of the Vorlons, they would naturally be the loyalist faction, or maybe "Guardians".
And then there are the extremists, like Kosh Ulkesh, for whom prooving the Shadows wrong has become more important than their role as teachers and protectors. Since these Vorlons lost sight of the true purpose for which they remained in our galaxy, they are the natural rebel faction. Maybe you could call them "Extremists" or "Fanatics" (blowing up planets and all that does sound pretty fanatical to me).
While this split is only hinted at in the actual series, the second and third books of the "Passing of the Technomages" Trilogy "Summoning Light" and "Invoking Darkness" specifically mention this division, with one group being more moderate, while the other is demanding the outright and merciless destruction of anyone touched by the shadows, with the latter faction gaining more and more support and ultimately gaining the majority with Kosh's death.
For the Narn, there would be those that prioritise rebuilding Narn and those that advocate the destruction of the Centauri above all, though it's hard to tell which ones are the rebels in this case. Maybe they could be called "Militarists" and "Preservers".
For the Centauri, the "Old Guard", lusting for a return to their old glory would make up the loyalist faction (Londo during the first three seasons, Cartagia and Refa being good examples), with the more peacefull faction (like Turhan, Londo between "And the rock cried out no hiding place" and his surrender to the Drakh or Emperor Cotto) making up the rebels.
The EA is pretty obviously split between the democratic pro-alien group and the xenophobic dictatorship of Clarke. The problem is, which are the rebels. In the series itself, Sheridan & Co where the rebels, but they remained true to the actual mandate of earthforce, while Clarke betrayed everything Earth and Humanity stood for, which would make him the rebel...
If there is ever going to be a Drazi faction, they would obviously be split into green and purple.