Ottilie Wilhelmine Roederstein (April 22, 1859-November 26, 1937) was a German-Swiss painter.
Biography on Wikipedia: https://en.wikipedia.org/wiki/Ottilie_Roederstein

The Sisters by Ottilie Roederstein
1900 / Oil on cardboard / 9″x7-1/5″ / Städel Museum, Frankfurt, Germany

Ottilie Roederstein on Artnet: http://www.artnet.com/artists/ottilie-w-roederstein/

Further reading:
https://kunstmuseumbasel.ch/en/agenda/blog/2020/56
https://awarewomenartists.com/en/artiste/ottilie-w-roederstein/
https://www.artandobject.com/press-release/ottilie-w-roederstein-swiss-woman-artist-rediscovered