French Apple TV apps from the US

Are you in Canada by any chance? The MD199C/A code seems to be for the 3rd generation Apple TV in Canada, whereas the -LL/A code is the part number in the US. I'm not aware of any differences between the two (other than the limitations on Canadian iTunes, such as more limited iCloud TV/Movie accessibility).

You can verify these numbers by adding the Apple TV to your cart in the US or Canadian online Apple Stores.

This is currently not possible with any default app.

As a workaround, Plex allows this if you set up a playlist (Play Queue) for each item and play the queue rather than choosing an individual video from a collection.