FastSnail HDMI Type C Adapter for Nintendo Switch

Might be better to wait for the Nyko dock. After you buy an AC adapter, it’ll cost the same or more. Not sure I’d trust that brands AC adapter. The official Nintendo one is $30. Same price as that HDMI adapter.
You can buy it on Amazon. No waiting, if you buy that, instead of the Nyko dock. I don’t need another dock right away.
Update
Actually, you will be waiting, it ships from China. Better off waiting for the Nyko.