Solution : https://service.sap.com/sap/support/notes/112029 (SAP Service marketplace login required)
Key words : 
transaction smlt   language -> 'schedule import' -> 'special imports' -> partial imports ->   'single tables', -> partial imports   -> single tables, important notebefore starting transaction smlt, car -xvf <path>/fixes/l31h06, job sap-language-import-job-3, thes<   tcpdb table exclusively concerns, 5a language import solution relevant, smlt -> schedule import -> menu, zcsa/installed_languages profile parameter, complete set   insert serpt
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