I would suggest you stay away from anything close to a full sized right or a "shortened and/or lightened" full sized rifle and get a dedicated youth rifle like ones that Henry, Savage, or Cricket make. My son was 8 when I got him a Henry Youth and he shot it till he was almost 12 and he is now 15. With a true youth rifle he was able to shoot properly it was the perfect size for him. Large sized or trying to make a basically full sized rifle to fit your daughter would limit her to shooting only from the bench and not offhand, sitting, kneeling etc. the LOP would be perfect for her and since all of the mentioned rifles are single shot she won't be going all Rambo wasting ammo. When she out grows it you can sell it and at least break even.
Also never ever ever get a scope or red-dot till she is really good at irons
scopes and dots are crutches
if you can shoot well with irons you can shoot well with anything.