Her Wikipedia article is here.
This portrait shows a plumed hat on a frizzy coiffure and a vee shaped neckline framed by a lace bertha as well as jeweled sleeves.
Keywords: Countess, Duchess, Reuss family, Wettin family, German, long frizzy coiffure, feathered hat, vee neckline, bertha, lace, earrings, jeweled sleeves