Answers
Please be aware that for Golden Visa applications, all documentation needs to be translated in Greek from an official authority. Usually the lawyer dealing with the application undertakes the responsibility to bring the document in foreign language to the translation authority.
Regarding the language requirement for the documentation, please be advised about the following: The documents that are required for the application for a resident permit must be submitted in Greek. Additionally to that, the documents issued by foreign authorities need to be certified. There are two types of certification: the apostille stamp for countries that are parties to the Hague Convention and certification by the consular of the origin country. For countries that are parties to the Hague Convention, and for which Greece has not issued a warning, the public administration accepts the Apostille stamp which is provided by the relevant foreign authority on the foreign document. For any countries that are not parties to the Hague Convention, a certification by the Greek consular in the country of origin of the document is required. The official translation of foreign public documents can be done in Greece by: the Translation Service of the Ministry of Foreign Affairs; a lawyer, who must be a member of a Greek bar association, with a certification of their signature by the bar association; or in the country of the applicant through a notarial authority, but this has to be certified and authenticated by the Greek consulate.
Foreign authorities may be your home country authorities. All the other documentation need to be translated in the Greek language.