Some additional info can be found the Dav.McIntosch great book the Unkhown Habsburgs.
Archduchess Elisabeth Franziska died early in 38 years old as she had poor health. Her widower married in 2 years her sister Gertrud.
Archuduke Hubert Salvator after WW I studied law at the Uni of Innsburck, and later administered the family estate in Persenberg.
Hedwig married Count zu Stolberg-Stolberg, whose family possessed large estates in Germany, and they settled in Tyrol.
Mathilde married late in life an Under Secretary of State in Austrian Ministry of Education. They had no children.