According to Official Guinness Records,
The most goals scored in the FIFA Women's World Cup final by an individual is 3 and was achieved by Carli Lloyd (USA) playing for the USA vs Japan in the 2015 Women's World Cup Final in BC Place, Vancouver, Canada, on 5 July 2015.
Carli Lloyd became the first woman to score a hat-trick in a senior FIFA World Cup Final and only the second person after Geoff Hurst of England in 1966. Previously Michelle Akers (USA) had scored two goals in the 1991 Final and was the only female footballer to have scored multiple goals in a World Cup Final.
For a complete list of 2015 records, please visit 2015 Guinness Records in Canada.