In People's Republic of China (PRC), all China people with People's Republic of China (PRC) nationality should use Chinese signature as their legal signature, so English signature should not be recognized. If only both parties have English signatures, this contract will not be established.
However, the other party has closed it. If there is a clear agreement in this contract: "This contract shall come into effect as of the date when one party seals it" or related clauses, this contract shall come into effect.