No images of real faces were used, but by devising prompts, it may be possible to create relatively close recreations of both Eri and Emma.
【base】
pink and white bodysuit,fitting bodysuit,shiny-bodysuit,pink Topswear,Golden coat of arms,white glove,short glove,gold line black bangle,silver belt,simple belt,gold buckle,square buckle,pink trim skirt,white skirt,mini skirt,Tight skirt,fit skirt,white pants,fit pants,long boots,pink boots,lowsole,
【helmet On】
pink helmet,round helmet,visor in helmet,
※It may be effective to include 【human girl face, human girl head,Expose Face,Expose mouth】 in the negative prompt.
【helmet off(japan ver./Eri)】
human girl face,human girl head,brown hair,long hair,straight hair,Asymmetrical bangs,high ponytail,pink hairScrunchie,white turtleneck,
【helmet off(USA ver./Emma)】
human girl face,human girl head,brown hair,parted bangs,long hair,Wavy hair,Hair over the shoulders,white turtleneck,
※If you're recreating Eri and Emma, adding【helmet,mask,visor,pink skin face,black skin face,silver skin face】to the negation prompt might be even more effective.