Example for Q42 (ru: "Дуглас Адамс")
Expected escaping:
"\u0414\u0443\u0433\u043b\u0430\u0441 \u0410\u0434\u0430\u043c\u0441"
Actual escaping produced by https://www.wikidata.org/entity/Q42.nt:
"\u00D0\u0094\u00D1\u0083\u00D0\u00B3\u00D0\u00BB\u00D0\u00B0\u00D1\u0081 \u00D0\u0090\u00D0\u00B4\u00D0\u00B0\u00D0\u00BC\u00D1\u0081"
It seems like UTF8 bytes get encoded as individual unicode characters, a kind of double-escaping. This is likely a problem with EasyRdf, but might have been fixed upstream already.
The discussion at https://github.com/njh/easyrdf/issues/175 seems related.
The relevant spec is http://www.w3.org/2001/sw/RDFCore/ntriples/#sec-issues.