Her woged form is the most withered and aged which is said to be sign of age in the Hexenbiest & Zauberbiest article. Couldn't she be over seventy or eighty years old based on that?
I think Frau Pech is the oldest. Her hexenbiest form is even more withered and wrinkled than Elizabeth's.
I think that after Frau Pech, its Elizabeth and Henrietta, and then Catherine, and then Adalind and Juliette/Eve
Frau Pech and Elizabeth might be close in age at least. The writers probably forgot their own rules too.
What do you think?