There's a lot of things going on here and I can give you my opinion based on what you wrote, but in person help from a dog trainer woudl be very helpful to you especially since you are novice puppy owners. In my humble opinion training classes are mandatory for all puppy owners and a great way to head off future problems a dog can have later in life.
1) Two females living together is tough and could be tough for their whole lives- altered or not it does not matter.
2) Raising two puppies together is also tough and the two need tim away from each other to develop normally.
3) There is always going to be a dominant female in a pack and a subordinate female. It's not man's job to decide which dog that is. Dogs do that on their own with their own language. Dominant dogs are not bullies though so if two dogs are picking fights, typically the one picking the fight is the subordinate trying ot be dominant, but not succeeding. In my house, I do not tolerate fighting, but my dogs get loud and seem to be fighting when they are in fact playing. Determining if it's playing or actual fighting isn't too hard- is one trying to get away from the other and they aren't being allowed to leave? Are they going after throats?
4) Each dog should have their own space to call theirs- a crate tends to be ideal for this. When yo ucan't supervise- the two dogs shoudl be crated and not have access to each other.
These are just a few things that may help out. Again, seek the advice of someone in person who can watch these two. Dog language is complex and puppy language is immature. It's hard ot tell if there's a real problem or not.
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Chelle and the rest of the crew including, but not limited to Kita and Taiko (the shiba inu wrestle maniacs), Adi (reserved and dignified tabby cat), and all 28 reptiles