There is no doubt that unmanned submarines are in the works. A very interesting project is the KM-STC10, intended for use by special forces. You can see it below. I have a strong suspicion that Aselsan or Meteksan has reached out to Kuasar Marin to collaborate for an unmanned variant.
There is also a few smaller projects ongoing, and there is a possibility that STM is already working on a large unmanned submarine.