But if I send Bitcoin to BTC-China could I withdraw it without get verified account ?
Yeah, you'll need to provide your ID for them to verify your account before you could withdraw.
So i need to provide my passport no matter which kind of currency i deposit/withdraw ? I want to trade only BTC <-> LTC <-> BTC on there, no fiat involved.
That I'm not too sure, but when you register with them they require you to fill in your passport details etc.