Hermit, Outlander, Sage, etc. all get a language trait from choosing that background. However, it's not made clear whether these languages stack with the languages that races provide, or replace them.
For example, a character playing as an Elf will get the following languages:
Languages. You can speak, read, and write Common and Elvish.
Alternatively, in the Outlander background:
Languages: One of your choice
Say a player was playing an Elf with an Outlander background. Which takes precedence? Racial over background, background over racial, or do they stack and happily coexist in a trilingual level 1 elf?