Seems that an implementation is in Journal application (https://github.com/liferay/liferay-portal/tree/master/modules/apps/journal )
Looking in https://github.com/liferay/liferay-portal/blob/master/modules/apps/journal/journal-service/src/main/java/com/liferay/journal/model/impl/JournalArticleLocalizationBaseImpl.java
I find:
* The extended model base implementation for the
JournalArticleLocalization service. Represents a row in the
"JournalArticleLocalization" database table, with
each column mapped to a property of this class.
that seems an implementation of internationalization recorded in a
separate table.
Looking in the JournalArticleLocalization table,
for an article il english/italian, I see the table in the screenshot below.
I'll go on investigating.
