How to report someone posing as a court judge to send documents to the plaintiff?

You can report the case to the public security organ.

Provide the public security bureau with relevant evidence of the criminal suspect's lawsuit.

Article 2 10 of the Civil Procedure Law stipulates that the procuratorial organ has the right to investigate and verify. This requires the procuratorial organs to investigate and collect evidence strictly within the framework permitted by law. In the case that false litigation may exist, if the applicant applies to the procuratorial organ for investigation or it has a significant impact on national interests and social interests, the procuratorial organ shall initiate the investigation procedure of illegal acts according to the application or ex officio.

Article 210 of the Civil Procedure Law The people's procuratorate may, when performing its legal supervision duties, investigate and verify the relevant information from the parties concerned or outsiders because of the need to put forward procuratorial suggestions or protest.