There is no grammatical gender in the English noun. The word benefactress may be used for a female benefactor, but it is not necessary except to specify the person's gender, which of course is a form of sexism.
Malefactor
Clot is not gender specific.
The opposite of dairymaid is dairyman.
Mistress is the opposite gender of master.
Newswomen is the opposite gender of newsmen.
benefactress
That would be a benefactress.
Benefactor is technically gender neutral, but benefactress is a specifically feminine form of the word.
Malefactor
The feminine form of "benefactor" is "benefactress." However, in contemporary usage, the term "benefactor" is often considered gender-neutral, and many people use it to refer to individuals of any gender who provide support or funding. As language evolves, the need for gender-specific terms is diminishing in various contexts.
Doctor is a neuter gender
Opposite gender of Filipino: Filipina
Clot is not gender specific.
The masculine form of "benefactress" is "benefactor." A benefactor is an individual, typically a person of means, who provides financial support or assistance to a person, organization, or cause. While "benefactress" specifically refers to a female benefactor, "benefactor" is a gender-neutral term that can refer to anyone who provides such support.
Opposite gender of a Filipino: FILIPINA
There isn't an opposite gender of farmer. A farmer can be either a male or a female.
An emperor is the opposite in gender to an empress.