this will go on for a while, but will settle.
tbh, i may be wrong, but i think the longer you keep them separate the longer the process will take.
i have introduced nebies to the gang a few times, and find the best way is just to slip them in at night, and treat them all the same from the start.
i just got 2 new girls too, from a lady who was keeping them in her wee garden, but the neighbours were complaining, so she rehomed them with me.
now, these 2 have never free ranged, so i have done the separate pen within the main night enclosure thing. i'm going to leave them like that for a couple of days as i am going away, then the second i'm back i'll let them in al together, and the newbies will follow the gang and learn to free range and come home to roost at night.
but i know fine there will be squabbles, you just have to accept that this is normal for chickens. its the fowl side of their natures!