Voice vs Genre isn’t really a thing. Since I have said that, let me explain. I saw someone on a forum saying that they were told they should know their genre if they want to find a manager or sell a script. They were concerned that sticking to a genre would stifle their voice.
Difference between Voice and Genre.
Your voice is the way in which you tell a story. It is the way you write action. It is the style of characters and the plots and struggles you put them through. All this is your voice. Genre is the voice of the story (pretty bad metaphor). Horror is a genre, we know it will be scary, we know people will probably die, we know characters will be in constant fear. How you tell that is your voice.
Understanding your voice.
I wanted to be the greatest teller of stories ever. I wanted (and believed) I would write movies that would have people diving into great lengthy analysis. But once I started writing it became obvious what my voice was. I write stories about people under pressure. The decisions they make and the errors. In my stories, people could have a happy ending if they made better choices. Not a guess. The better choice is right there. They continue along the path to destruction. That is my voice. It comes across in the way I handle dialogue and the way I describe action and locations.
Voice and Genre.
Your voice will lead you in the direction of a genre. Certain genres cannot be written by people with a certain voice. I cannot write comedy. That doesn’t mean I am not a funny person. My entire family is witty. My brother is a professional comedian and lectures comedy at college. But the voice of my writing is drama, dark and crime.
You just have to be honest with yourself. What do you think when you think of a story? When you are not forcing your work, what does it look like? What form does it take? We can all sit and force ourselves to create a genre. I could write a romantic comedy. It will not be good. But I can write it.