WPML is a WordPress plugin to enable multiple languages in your site. It is a robust feature complete system. I have developed many sites using it and I have yet to come up against something I couldn’t fully translate.
Term Management Tools includes support for WPML-translated terms as follows:
Changing the Taxonomy
When terms are moved from one taxonomy to another, any translations are also moved, and the translation linkages are preserved. For example, here is the WPML translation status of one of my development testing sites, showing the “before” state of the categories:
And here is the after state, after the “Parent Term EN” term (and all it’s children, automatically included) were moved to the “Hierarchical” custom taxonomy:
Note that other than the “Default EN” category (which wasn’t, and in fact can’t be, moved) the records are the same.
Here is the key to little icons in case you’re curious:
means a translation exists and can be edited
means the translation is missing and can be added
means the term in that language is the primary term