Problem/Motivation
Menu links in Drupal 6 are translated using i18n_menu submodule of the suite i18n, we need to migrate those respecting the language settings.
Proposed resolution
There's an element called langcode in the options array of the menu items: $item['options']['langcode'] and it's saved using i18nstrings in a key-value-language table.
Only title and description are stored with the i18nstrings module by using this tokens:
'menu:item:'. $mlid .':title''menu:item:'. $mlid .':description'We probably need to have a plugin source that gets all this information from the {i18n_strings} table.
Original report by Ryan Weal
i18n menu (D6/D7 i18n contrib -> D8 menu config). This contrib module provided a setting where a site could have separate menus for each language and display only the desired one in a section. In cases where separate menus are used the menu links often do not have a language setting.
Postponed on #2178703: Migrate D6 menu links