This is Robin from Honkai: Star Rail. This includes both her base and Summeretto forms/outfits.

Her base prompt:

r0bn, blue hair, multicolored blue-green eyes, hair between eyes, halo, head wings,

Her outfit:

white gloves, bare shoulders, blue footwear, strapless dress, white-purple dress, detached sleeves, short sleeves, jewelry, purple footwear, earrings,

holding staff,

Summeretto:

swimsuit, sandals, white-blue bikini, navel, blue choker, toenail polish, toenails, sunflower, sarong, yellow flower, jewelry, blue hair, hair between eyes, bare shoulders, white footwear, nail polish, strappy heels, hair ornament, leg ribbon,