Because of you is usually followed with more information. Also, it's your fault is usually a negative thing where 'because of you' can be either negative or positive. It's your fault that I lost the game. Because of you I lost the game. OR. Because of you I won the game.

Both are correct, depending on context.

It's your fault that we lost the game.

Because of you and your weak kicks, we lost the game.

Joan is in her room crying because you yelled at her.

It's your fault that Joan is upset.

They're both correct, but they're not the same: -- it's your fault = es tu culpa (eres culpable) -- because of you ... = gracias a ti ...