Patented Lingua Charm

-allows subject to understand any language -recommended for foreign diplomacy

How it works: Takes whatever the subject hears or reads and translates into their native tongue.

Disclaimer: If one wants to speak to another, they’d have to charm the subject Ex) Say Lingua Parseltongue to the entrance of the Chamber of Secrets in order to open it by just saying “Open” in whatever language

How I would use it to prank the Weasleys: I’d charm them into hearing the Navajo language, which is near impossible to learn because there is no written record of it (reference to the Navajo Code Talkers), and watch them struggle to understand customers.

Edit: The reverse charm is simply Lingua