The famine name Neta came out from the German names Ageneta or Agnes.
In the 17 century we can find it in the book "Beit Shemuel" about jewish names,
Alexander Beider in his book" Ashkenazic Given Names" write that this name was find in 1347 in Frankfurt
and after this time also in 1546 in Prague and in more towns in Europe.
My conclusion is , that famine name Neta was very old and where used from the middle ages in Jewish families.