Adding to an existing game should be fine, however removing it may cause factions to not load any ships or stations. I have never tested this myself. I'd recommend making a backup copy of your save file then try removing the faction packs. Should you encounter any game breaking bugs you can then revert to the old mod load order and restore your save file.

Question. in General removing a faction pack will it break the save? or revert to a default? I may have installed a few to many Faction packs :) you seem active so was hoping you may be able to assist

Ok, np.
I just saw that you did make alot of faction mods already and I was wondering if you were going to make one for stargate.

Sorry not currently looking at making any packs, life has been rather chaotic for me atm. Maybe in the future when I'm in a better space I will look into it.

Just wondering, have you thought of making a stargate faction pack?
Im someone who love stargate and I would love a faction pack for stargate.

Yeah, I checked that already. I downloaded all the available faction packs, and came across one of them (By Battlestar Galactica), and got punched in the face, because they are incredibly strong and hit five times more painful than normal bots on high difficulty

These will not replace existing discovered factions, but they have a chance (not guaranteed) of appearing as other undiscovered factions.

Could you give me a hint: will these factions appear in a galaxy that has already been generated, but not yet very explored, or do I have to start a new game?

The faction pack just needs to be active in the mod list. Since factions are somewhat random it is chance that you'll come across a faction using this shipset, it shouldn't be too unlikely you'll come across them tho.

I love these ships and use them myself .. sadly i cant seem to get this mod to work ... Do i require anything to make it work ingame or just activate it in mod list ? ... or am i just having bad luck in finding a fraction using these models ?