When displaying pages and other content, each language version of content is displayed as a separate item. When editing pages and other content, each language version must be edited separately.
However, each language version of a particular piece of content is only another modified version of that same piece of content. Therefore, when ANY language version of a piece of content is added to a bundle, or push published via Workflow, ALL language versions of the contentlet will be pushed in their current state on the sending server.
Note that content will never change state because of a push publish operation. If a piece of content exists with an unpublished version in Spanish and a published version in English, and EITHER language version is pushed, then the Spanish version of the contentlet will be pushed to the receiving server in its unpublished or “draft” state and the English version will be delivered to the receiving endpoint as a published piece of content.