Document Legalization Act for the Ministry of Foreign Affairs and Overseas Missions Article 10

The overseas mission shall only provide legalization of documents issued within its jurisdiction. However, an exception shall be made if the application is deemed a special case and document verification is not difficult upon approval from the Ministry.
中文原文 外交部及駐外館處文件證明條例第10條
申請驗證在國外作成之文書,應向管轄該文書作成地之駐外館處為之。
但受理申請之駐外館處認有特殊情形,且無查證困難,並報經主管機關核准者,不在此限。

English translation for reference only; the Chinese text prevails. Not legal advice.