No, in Uruguay is obligatory to have the legal licence plate in the back. You can use the other legal licence plate they give you in the front also or put whatever you want.
If a state issues two license plates, they BOTH must be displayed on the vehicle - one on the front and one on the rear. If only one is issued, it ALWAYS goes on the rear of the vehicle.
Texas law (Transportation code, 502.404) requires all road vehicles to display a front license plate, unlighted. The location of the plate is undefined.