The back sprite of Bianca is only in her professor juniper's assistant outfit (BW2 Outfit), but someone changed it to her casual outfit, I found her casual back sprite somewhere online. And we also have her VS, Xtransceiver and battle sprites
There may be some fanmade sprites for actions too, but I think her walking fast/running sprite is available in the game after professor juniper gives pokemon catching tutorial you can see Bianca & cheren running towards the accumula town
It would be more better if someone can make a patch for it instead of a cheat code...
I wish I knew how to make a patch XD