Entity Translation's Language Switcher (Content) is not showing
if you want to activate the Language switcher for User or for Content you have to go to:

../admin/config/regional/language


Use the second tab "Detection and selection" and activate for "Language switcher user" the first section:


User interface text language detection - Enabled: YES


After that, you will see the language switcher.

For your "Language switcher content" you have to activate the other section:


Content language detection - Enabled: YES