If you run the mongorestore with the database name in the uri you will get an error. For example: 

mongorestore --drop --uri mongodb://localhost/mydb --collection languages ./languages.bson

{{ 2020-07-17T14:17:09.142-1000 Failed: cannot restore a collection without a specified database}}

However, if you add --db, which the documentation warns you should not do, it works just fine.