Geonosian Engineers is a technology in Clone Campaigns that is unique to the Confederacy, and can be researched at the Hvy Weapons Factory in Tech Level 4. It costs 450 Food and 500 Nova, and gives Hvy Weapons Factory units +10% speed. In addition, their reload speed is reduced by 0.25 seconds, though the latter improvement doesn't apply to the Pummel and Hvy Pummel.
This technology makes the player's Heavy Weapons slightly deadlier than before. It's a useful upgrade, but not game-changing.
"This technology bolsters its Heavy Weapons units, improving their movement speed by 10 percent and improving their rate of fire. Geonosian Engineers may be researched at the Heavy Weapons Factory in Tech Level 4."
—Manual description