Linguist

As a Minor role, you learn two languages of your choice. In addition, you gain the ability to understand fragments of languages that are adjacent to languages you know.

As a Major role, you learn four languages of your choice. In addition, you gain the ability to understand fragments of languages that are adjacent to languages you know. Also, you gain advantage on Charisma (Persuasion) and Charisma (Intimidation) checks when talking to a person using their mothertounge if it isn't common.
At level 8 you can create you own simple language that can be used to communicate secretly with your companions. It takes a week to teach it as a Major role and two weeks as a Minor role. In addition as a Major role, you can ably create written ciphers. Others can't decipher a code you create unless you teach them, they succeed on an Intelligence check (DC equal to your Intelligence score + your proficiency bonus), or they use magic to decipher it.

Knowing the language, and speaking the language are two copletely diffrent matters. But you do both. When it comes to reading and writing you are the expert.

How often do you find a passage in a book and think to yourself, god I really wish I could read this. With a Linguist in the party, wonder no more. You can read just about anything and understand speech from anywhere from heaven to hell. You know that the mothertounge holds a special place for any creature, and you can use it to your advantage. I Know that not everything is a secret code or scipher, but I really think that this time is different!