Unknown characters cosplayed in Akihabara in 2013 photo

hi! here are my guesses

for the second character, i'd like to think that woman's cosplaying Marie-Antoinette from "Rose of Versailles''. the dress is really similar, identical even. however, the only discrepancy is that Marie-Antoinette is never displayed wearing a straight blonde wig, as of now, that's my only guess for this one

the third character is probably Tsumugi Kotobuki from ''K-On!''. not my most accurate guess ever, considering that the costume is slightly different, but that's the most i can help 



btw, have you tried reddit? i know there's a lot of anime fans on there that could maybe help you in some way..