I was wondering if the Saurian with the efficient trait will stack onto the Borg officer with the efficient trait. Would be helpful to know before I save up/then waste EC on it since they are pretty expensive
Yes, both Efficients will stack as long as you have both BOffs placed on the ship. PatricianVetinari has an excel power calculator you can download from here that shows you how the power changes on different ships depending on settings and Skills, and Efficient. It can be quite helpful.