>>518151741.5 month player here.
You use sync orbs to exchange for energy, but you only have 60 available energy to select panels. So once you have exchanged enough sync orbs to get 60 energy for your unit, you can then select what passives to buff your unit.
You can also create different builds as you will not have enough energy to be too overpowered. There's an option switch grid builds.
But builds only work more effectively when you get duplicates of each unit in order to unlock more panels, so most 1/5 units are only as good as their level and their 6*EX boosted stats.
For the other experienced players, I imagine I should dump my only Tech Candy on SS Red as the more obvious choice, right?