"He is my favorite writer."

Translation: Він мій улюблений письменник.

[FelipeNandes]

So is письменниця a female writer and письменник a male writer?

[greg.mort]

That's correct

[DerekWilson9570]

Why not put є for "is"?

[greg.mort]

Usually it’s omitted

[yaroszko]

If I am a girl shouldn't it be він моя улюблена письменник since the 'my favorite' part of the sentence refers to a female?

[Olly_1052]

Even if you are a girl, you should say "Він мій улюблений письменник" (male writer) or "Вона моя улюблена письменниця" (female writer).
The part "my favorite" refers to "writer" here, not to you.

[IsisV_]

It should be вона моя улюблений письиенника iirc

[Olly_1052]

Вона моя улюблена письменниця.