With these and all the necessary procedures (driving license and insurance policy) of the original car, you can go through the transfer procedures. However, it is best for both parties to be present in person. On the one hand, it is to clearly understand the ownership of used cars, and also to avoid contradictions that cannot be confirmed or resolved after the transfer.
Legal basis: Article 54 of the Regulations on Motor Vehicle Registration, the owner of a motor vehicle may entrust an agent to handle various motor vehicle registration and business, except for applying for a new motor vehicle registration certificate. If the owner of a motor vehicle is unable to apply for a new motor vehicle registration certificate due to death, exit, serious illness, disability or force majeure, he may entrust an agent to apply for it on his behalf with relevant certificates. When an agent applies for motor vehicle registration and operation, it shall submit the identity certificate of the agent and the written authorization of the motor vehicle owner.