SQL queries to detach WPML duplicates and translate them separately.

wpml-detach-duplicates.sql

# Select all posts which are duplicates of a language. 
# The language parameter is to only select by the new language (not the original duplication language).

SET @lang_code = 'da';

SELECT pm.*, p.post_title, p.post_type, icl.language_code
FROM wp_postmeta pm
INNER JOIN wp_icl_translations icl ON icl.element_id = pm.post_id 
INNER JOIN wp_posts p ON p.`ID` = pm.post_id 
WHERE meta_key='_icl_lang_duplicate_of' AND icl.language_code = @lang_code;


# Same as above but to delete instead of select. The above should be used first to 
# make sure that you don't delete the wrong rows ;)

SET @lang_code = 'da';

DELETE pm
FROM wp_postmeta pm 
INNER JOIN wp_icl_translations icl ON icl.element_id = pm.post_id 
WHERE meta_key='_icl_lang_duplicate_of' AND icl.language_code = @lang_code;