The second sentence is translated literally and does sound awkward.
You would never yell out "Female liar!". English has no gender in its nouns as such unlike French which seems to assign a gender to every noun....[why is "the table" translated to "la table" and not "le table" is beyond me]
The proper translation would just be "liar!". The person being shouted at would establish the gender.
There must be a slang term for female liar but for the life of me I cannot think of one right now. Although in Australian slang a "leighster" is supposed to be a female liar but that would only apply in that country, to my knowledge.