Way long ago ships could shoot from under a forcefield with no penalty.
Then it was changed to do damage to the protecting forcefield. This did not apply to the ff's projected by Shield Bearers.
Then it was changed to not do damage to the protecting forcefield but to do 1/4 damage to the target. This does not apply to the ff's projected by Shield Bearers.
Later on a few other ff-types were introduced that don't have a penalty (namely Riot Starship Shields, Avenger Shields, Hybrid Shields, Spirecraft Shield Bearers, and all the FS capital-ship and city-defense shields).
In any event, when it comes to defending a command station against heavy attack while the fleet+static-defense deals with the attackers, the absolute #1 most effective tactic I've ever found is piling tons of mkII and mkIII ff's on top of it with a bunch of engineers hiding under them to repair them; there's a delay between last-damaged and can-be-repaired but if you have enough "layers" and can keep the overall incoming damage below a certain critical point you can basically tank forever.
Without ff protection even a military command station goes *pop* waaaaay too fast.
Do forcefields hinder Military Command Stations' ability to shoot effectively? Do they also get 1/4 to their firepower if under a forcefield?
Yes, that's correct. But the translocation effect is unchanged.