English Translation
These earphones don’t work.
Kopfhörer = headphones
Ohrhörer = earphones
These earphones don’t work.
Kopfhörer = headphones
Ohrhörer = earphones
There are multiple things to say about this:
Literally, the correspondence is obviously as you said, but in practical usage the borders are a lot more blurry.
Also: In german, the over-the-ear variety is usually “der Kopfhörer”, i.e. singular. If you use it in the plural like that, it can quite possibly refer to in-ears (or more than one set of headphones of course).