After the one year war in U.C timeline, the Earth Federation Space Force E.F.S.F had formed up an elite regime to take control of the spacenoids. However, the ruthless methods of Titans had caused many to detest them. The mobile suit belongings to Titans usually are sprayed in the sinister dark blue colour. I don't remember seeing the Gundam RX-78-2 in Titans version on the animation. It's just another variant of 20th Anniversary Chogokin Gundam RX-78-2. The Titans Gundam mobile suit shown in Zeta Gundam anime is the Gundam MK2.