Intro 

Star Wars: Interregnum is an upcoming mod for Sins of a Solar Empire: Rebellion that builds off of the highly successful Enhanced 4X Mod. Fleeing the unknown terror that is chasing the Vasari, the factions of Sins of a Solar Empire stumble on a temporary wormhole that takes them to a galaxy far, far away. The sudden arrival of armadas with trillions of refugees and thousands of warships between the events of Episodes 5 & 6 forever alters the Star Wars universe and plunges the galaxy into an unprecedented period of chaos and violence.

Features
4 new factions: Interregnum will feature 2 new races each with 2 subfactions like vanilla Sins races...

• The Galactic Empire is the remains of Palpatine's Empire now headed by Darth Vader, and enjoys a powerful industrial base and perhaps the most powerful fleet of all factions. However Vader's poor political skills and the feeling that the Empire is being crushed from all sides has left the Empire with extremely poor morale, and further defeats may start damaging the Empire's war effort. 
• The Imperial Warlords are an umbrella faction that represents the various Empire factions that have operational independence, whether they've gone Rogue to serve their own agenda or are acting under orders in special circumstances. While lacking the legitimacy and infrastructure of the Galactic Empire, this has forced the warlords to use their forces more wisely than the sometimes brutish Imperial war machine. And the Emperor's fondness for conducting research in remote locations, along with Vader lack of interest in major R&D projects has allowed the Warlords to get access to many powerful technologies that might more than make up for their shortcomings. The player will also be able to choose to ally with one of the Major warlords for additional bonuses, mainly Grand Admiral Thrawn, Grand Moff Ardus Kaine, Warlord Zsinj, and Director Yasanne Isard.
• The Rebel Alliance is the original military branch of the Alliance to Restore the Republic and continues to fight the Empire much as it did in the Galactic Civil war. Preferring hit and run attacks and strikecraft superiority along with some innovative and dirty tricks, the Rebels are one of the most unique factions and are extremely difficult to stamp out.
• The New Republic was created by Rebel sympathizing planets after the Empire was forced to abandoned the Outer Rim following the emergence of the Sins races. Fearing that the Rebels would not be strong enough to protect them if the Empire tried to conquer them again, the New Republic has decided to create its own conventional armed forces from scratch. While this focus on new institutions leaves the New Republic vulnerable and disinclined to attack early on, once it gets going its powerful new warship designs along with its substantial economic and cultural strengths make the New Republic an extremely competent and well rounded faction with few weaknesses.

Superior Gameplay: As a successor mod to the Enhanced 4X Mod, Interregnum will support all the gameplay enhancements found in that mod, including...

• Hero Units: Both Sins and Star Wars factions can call in their most powerful champions to turn the tide of battle.
• New Planets and Random Encounters: Truly Explore the Galaxy far, far away with an expanded array of planet types, some of which will be populated with everything from Rogue Imperial Moffs to abandoned Republic era fleets to Mandalorian raiders.
• Improved Civics, Economy, Diplomacy and Espionage: Don't feel like just blasting your opponent? The Enhanced 4X substantially fleshes out the noncombat side of Gameplay with things like improved culture, embassies and spying.
• Customization: From adding upgrades to your favorite capitalships and titan to a library of minimods to customize your gameplay experience, 
• Upgrades to existing factions: Players totally new to the Enhanced 4X series of mods will find the familiar Vanilla races they know have all gotten an upgraded. All factions of received new techs, faction and racial bonuses, new starting units and other alterations that encourages more diverse gameplay.

Unit and Character List

See this post

Story

• Part 1 - The Journey
• Part 2 - The Battle of Endor
• Part 3 - Disintegration
• Part 4 - New Alliances
• Part 5 - Stalemate
• Part 6 - Dawn of Crusades
• Part 7 - Deadly Dealings
• Part 8 - Converts and Exiles
• Part 9 - Terrors from the Void

Progress

With the third alpha release, the Rebel Alliance has been added, meaning this mod can now be used to relive the Galactic Civil War as well as the current war with the Sins factions. The militia and pirates have also been replaced with Star Wars versions; now the vast majority of material on the game map is clearly from a galaxy far, far away.