Configuring translations for DX8
To use translation with DX8 you need to configure your website with the following settings:
1. Enable content translation
Enable Drupal 8 core "Content Translation" module. You can do this by going to "Extend" and then searching for "Content Translation" and enabling the module.
2. Enable entities to be translated
Next, navigate to "Configuration" > "Regional and Language" > "Content language and translation" in the admin menu. Here select what entities you want to translate for example select "Content" and then scroll down, then select the "Content Type" you want to translate, in this example "Basic Page".
3. Disable the Layout Canvas field from being translated
Next make sure the DX8 Layout canvas field is not set to translatable. Translation of the field is not supported as it is a entity reference and we don't want to translate the field but the underlying entity. Make sure to follow this step before translating any content or you will end up with content referencing multiple Layout canvas entities which can result in potential loss of data.
Go to Content language (/admin/config/regional/content-language) and make sure to uncheck any Layout canvas field for every bundle that you have enabled.
4. Enable translation for the Layout Canvas entity
Enable translation for the Layout canvas entity type and make sure you check "Hide non translatable fields on translation forms".
When reverting a piece of content that has non translatable fields, you will be asked to if you want to "Revert content shared across translations", when using DX8 layout canvas field you should always check it or implement 'hook_entity_bundle_info_alter' so it's always checked. You can find more information here: https://www.drupal.org/node/2938191