This is an original gown from the early Regency, accented with a delicate tulle overlay and featuring slim sleeves. I believe the original garment is in the Kyoto Museum collection. *Would need different sleeves.
What a lovely summery Regency gown. My heroine Nora always wears a big bonnet on her walks.partly because ladies always wore hats out, but also because she's hiding her face from the people stalking her.