Menu translation in Drupal 8

Menus in Content language and translation

1. Navigate the menu to Configuration >> Regional and language >> Content language and translation (admin/config/regional/content-language)
2. Under "Custom language settings"
   1. Select the "Content" and "Custom menu link" check boxes (don't hit save yet, an Ajax call will return new form fields to the page).
3. In the "Content" section that appears below, select the "Translatable" checkbox for the content types and fields desired.
4. In the "Custom menu link" section that appears, select the "Translatable" checkbox for the menus desired.
5. Lastly, select "Save configuration" button at the bottom of the page.

Translate menus options

-Go to "Structure >> Menus" page. You will see the list of the menus.

there is drop down button in front of each menu. Select the "Translate" option.

-In "Translate Menu" tab, Click the "Add" button in front of the second language.

-Add "Label" translation here, and "Save translation".

At this stage we have enabled content translation, Menu translation, Added translated content. Now we have to add the menu item translation. this is little tricky.

Translate a menu element

Go to "Structure >> Menu".

Click the "Edit Menu" in front of the menu name.

List of the menu links will be displayed on the page.

Click the "Translate" option in front of the menu item you want to translate.

List of enabled language is displayed here. click the "Add" button in front of the language.

Add "Menu link title" for translation.

In "Link" autocomplete field add the title of the translation for node.

Click "Save" button.
 

Repeat the process for all the menu items. And you are Done.

Check the menu items are displayed properly as per the language selected in language switcher.