A bit hard to describe this in the topic.

If you queue research on starbase modules, it immediately allows you to assign those upgrades to the starbase structures. If you queue enough upgrades to max out the Starbase, they will never start building once the research is finished.

For an easy example, use an Argonev.

Give it full weapons/armor research, leaving 3 slots. Start research on Remote Construction and Docking Booms. Immediately queue these actual upgrades (2 ranks of Construction and the Booms). When they finish research, the Starbase will not construct them. It will remain stuck in the queued state. You have to cancel all the upgrades and re-do them before it starts building.

Unfortunately, I haven't saved right before I played around with it so I don't have an easy save, but if you guys need one I can make it.