Yes, NVIDIA is working towards certifying USB-C adapters from several manufacturers on Turing products. Certified adapters will be available in early 2019.
In the meantime, customers can buy the below adapters that NVIDIA has tested the following adapters for for high-level basic functionality with GeForce RTX graphics cards.* Please note that these adapters have not yet completed NVIDIA's robust certification process, but have passed basic functional testing.
*Note that while NVIDIA has performed basic functional testing, we cannot guarantee the compatibility of these adapters.