The K6 has a USB-C port for charging. Of course, they bungled it and it doesn't have the CC resistors to trigger PD chargers, so you need an A-to-C cable, or some soldering skillz. Other than that, they are reported to be identical hardware.
Soldering skillz are always nice to have but the amount of Chinese 'USB C' gear that skimp on the 5.1K resistors is truly enormous, and adding them gets old really fast. Some designers even combine cc1 and cc2 to save 0.01¢ on the second resistor, with predictable results..
They probably don't know they need them. A lot of stuff is just copy-pasted from old reference designs that used micro usb and then they slapped a USB-C connector on for marketing purposes.
If you've been an electronics engineer long enough to be able to design this radio, you almost certainly know the resistors are needed, or can discover it with a single Google search ("PCB design micro USB to C upgrade").
A more likely story is cost savings. It's cheaper not to support it, from an assembly and testing point of view.
Yes it has a usb-c port on it which you can charge with a type-a to type-c cable.
The problem is that it violates the spec by omitting the resistor and you can't charge it with a c to c cable. That's where the frustration comes from.
A review from Amazon on UV-K5: "Warning though, the USB-C port feature is misleading in some way: you can't get it charged with whatever USB-C cable you have, it needs to be a USB-C power-only cable with USB on the other end (like the one provided). If you try USB-C to USB-C from your Mac it won't work. Also, USB-C direct charging can only charge it to max 80%. Other than that, this is quite a nice radio well built."
Sigh, won't buy any electronics that can't just charge USB-C without bs..