If you go into the Combat Overview window (the crosshair icon) you can set up the fire controls on your ships with weapons and targets, and then copy those weapons settings to either every ship of that class in the fleet, the system, or your empire. Targets can be copied to the same fire control of all ships of that class in the fleet, or in the system. You can also set ships to synchronize their fire, auto-fire, order fleet-wide firing and cease-firing, and activate and deactivate sensors and shields.
Apologies if you already knew all that, I wasn't sure if you meant the Individual Unit Details window or the Combat Overview window. Better safe than sorry!
