Not hard just nerve racking for the people. They have to establish the pecking order but they will work it out.
Look for some her same age. Keep a fence or something between them for a few days. Feed them side by side with the fence between so they can see that there is plenty of food to go around. That will help them not see each other as competition for resources.
Then when they start more or less ignoring eachother and you have time to spend with them, remove the barrier. There will be pecking, maybe scratching but as long someone is willing to run away they will be fine.
I have added to my flock 5 times now and no serious problems. No one got hurt beyond a couple lost feathers. The only fights I felt the need to step into was between a broody hen and a new flock member and when I added my roos there was some "not so gentlemanly" behavior to my ladies.
Don't be scared of adding birds. There are lots of people that have noticed "depressed" symptoms in their show birds when they are taken from their flocks. She will be happier with feathered friends.
Edit: I use a leaf rake to brake up fights. Kinda like a moveable small fence. My hands are too delicate to get between fighting chickens.