The name wieners and hot dogs are usually used interchangeably to mean the same thing for the same hot dog.
However sometimes wieners can be the hot dogs that are smaller than normal sized hot dogs which I've seem some in stores.
I've seem some small hot dogs that were called wieners in stores in small packages while the larger hot dogs were called hot dogs.
In Vienna, a city in Austria wieners are typically thinner and longer with an edible casing.
Wieners and hot dogs are sometimes the same thing in some countries while in other places they can be a different style of hot dog.
Either way they are both hot dogs.