Coloured UI for Sins of a Solar Empire II is a free mod designed for Windows that enhances the user interface by modifying the color scheme of various icons. This mod focuses on changing the icons related to ship orders, planet upgrades, and construction upgrades to align more closely with the color palette of the Rebellion UI. Although it does not alter the research tree icons, it effectively changes the golden borders and arrows that indicate researched items, aiming to make unresearched items easier to identify. The mod is particularly beneficial for players who want a visually cohesive experience while managing their fleets and planets.

In addition to the color changes, the mod introduces distinct color variants for different fleet movement commands, improving clarity during gameplay. For example, standard moves are represented in blue, fleet moves in green, and fleet-wide moves in purple. Engagement range indicators also utilize color coding, with hold positions in blue, close engagements in green, and free engagements in orange. These enhancements provide players with a more intuitive interface, allowing for quicker recognition of fleet settings and overall improved gameplay experience.