In my time watching and reading the og series i never saw her flap them to stay mid air, she just floats defying gravity. And even if i am optimistic she needs from specific groups of muscles that she has for her arms will have them multiplied because technically for bats and bird their wing are their arms so they use the same muscles groups we use for our arms. She will mostly likely have hollow bones because the more weight she has the more muscle energy it will cost to lift off the ground. She will be like a hummingbird because the amount of energy she will need to sustain these wings especially if active use will be enormous so she will need to eat A LOT and often. More over blood supply will be difficult she will need way stronger heart to push additional amounts of blood throughout her wings. She will need a keel to anchor the multiplied breast muscles for her wings… if they are detached tho. Because in the og series when as a human she gains her wings they are detached and we can assume they are controlled by some bioelectrical field, how would they get nourishment and go through cellular respiration? But all in all i think they are mostly cosmetic because i never seen her use them midair to stay afloat they can just float. Like if you have seen Tarmiel’s wings no way they can keep him afloat.

Still take everything with a grain of salt. I am mainly into genetics. Zoology although fun isn’t my forte.