Solution : https://service.sap.com/sap/support/notes/505906 (SAP Service marketplace login required)
Key words : 
importing support packages terminates, component bc-db-mss, required service packs/hotfixes, sql server-specific procedures, duplicate key reason, code point comparison, convert individual databases, 'duplicate key errors, homogeneous system copy, binary order based
Related Notes : 
       
| 1019320 | sap_update_MSSDBSTATT Cannot resolve collation conflict | 
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| 600027 | Installing the Corrected MS SQL Server Collation |