Of course there’s no actual official ‘china export’ mark and that is just what some Chinese factories were claiming when they were caught slapping a (accidentally mis-spaced) CE conformance mark on their products! The EC made a statement on this back in 2008 [1] so everyone knows what game they are playing.
1. https://www.europarl.europa.eu/doceo/document/P-6-2007-5938-...