as i said before , this is awesome you know , i'm looking forward to play it , and julia's model , but one of my friends told me that the one of the foot of Julia is bigger than the other a bit
That's just an 'optical illusion'. Sort of. It looks that way because of the angle the image was taken at.
I know I'm not Proximity, but I have some experience in 3D modelling so I'll explain why one foot can't be bigger than the other:
When working with 'symmetric' 3D models, concept artists often only flesh out one half of the character. This image is imported as a texture on a plane inside the modelling software (3DS Max or Maya or whatever) and a 3D model is created in relation to it. Once you're done fleshing out that half of the character, you mirror it and snap the vertices together in order to get a whole model.
So, as you see, the feet
must be identical, unless the concept art demands asymmetry (in which case the guy modelling the character could just go in and do 'the thing' that needs to be done).