I have the Anker USB C adapter that has the transformer prongs to fit into most plug types. I really, really like the design and have used it on multiple continents now. As others have remarked, unfortunately the big drawback is that it's only rated for 20W which is basically only enough for a single small device like a smartphone or kindle, and too weak for larger devices like most laptops or a nintendo switch, etc. But it does have extra US-prong holes so you can plug and adapter into it. What I've done is bring a separate 30W single port GaN adapter, so combined I get 50W and don't need to carry a plug adapter of any kind. It works okay-ish, but I really hope Anker comes out with a slightly more powerful model. Even 30-45W or so would cover the needs of most people, while 20W is unfortunately just a bit too underpowered to be a true all-in-one adapter.