If you mean a Capship that doesn't move, then all you need to do is make it a weapon platform and it'll attack any hostile in range. This is from my mod, I don't know if it works with FLE as I don't use it.
Put this in solararch.ini
[Solar
nickname = l_dreadnought_weaponplat
type = WEAPONS_PLATFORM
DA_archetype = ships\liberty\li_dreadnought\li_dreadnought.cmp
material_library = ships\liberty\li_capships.mat
material_library = fx\envmapbasic.mat
envmap_material = envmapbasic
LODranges = 0, 600, 800, 1200, 2000, 3000, 6000, 20000
surface_hit_effects = 0, small_hull_hit
mass = 100000.000000
solar_radius = 400
shape_name = NAV_smallstation
destructible = true
explosion_arch = explosion_rh_battleship
hit_pts = 69300
Put this in the loadouts.ini in the Solar folder
[Loadout
nickname = li_dreadnought_Wplatform
archetype = li_dreadnought
equip = infinite_power
equip = ge_s_scanner_02
equip = li_battleship_turret01, HpTurret_L1_01
equip = li_battleship_turret01, HpTurret_L2_01
equip = li_battleship_turret03, HpTurret_L3_01
equip = li_battleship_turret04, HpTurret_L4_01
equip = li_battleship_turret04, HpTurret_L4_02
equip = li_battleship_flak_turret01, HpTurret_L4_03
equip = li_battleship_flak_turret01, HpTurret_L4_04
equip = li_battleship_turret04, HpTurret_L4_05
equip = li_battleship_turret04, HpTurret_L4_06
equip = li_battleship_turret04, HpTurret_L4_07
equip = armor_scale_0
equip = SlowLargeBlue, HpRunningLight15
equip = SlowLargeBlue, HpRunningLight17
equip = SlowLargeBlue, HpRunningLight33
equip = SlowLargeBlue, HpRunningLight09
equip = SlowLargeBlue, HpRunningLight11
equip = SlowLargeBlue, HpRunningLight34
then put this in what ever system you feel like.
[Object
nickname = Lib_dread_wplatform_01
ids_name = 261164
pos = 80978, 0, -50343
rotate = 0, 140, 0
Archetype = l_dreadnought_weaponplat
behavior = NOTHING
ids_info = 66171
visit = 0
reputation = li_n_grp
difficulty_level = 10
loadout = li_dreadnought_Wplatform
pilot = pilot_solar_hardest
Change the "pos =","rotate =" and "reputation=" to suit your system. This will put a Liberty Navy Dreadnaught in your system that acts as a weapon platform, you can do this to other Capships, all you have to do is make entries like mine but using the models and loadouts for the other ships.
**shuffles of with a new headache**