Iirc that requires a usb connection at least in the first instance right? I guess only one way to find out if the usb c charging port on the Chromecast dongle supports any kind of data transfer
The answer is yes it does, this is how I did it. Maybe you can prove me wrong but I don't think I've ever seen a USB-C port that was incapable of data transfer, I actually thought it was part of the standard
I just install apps on my android tv with adb. But it all sucks, no useful alternative app store has an actual useful UI that works on the big screen. Updating is a pain, there's an app or two that help but they all a pain because it's almost impossible to navigate on the big screen with a remote control.
Not sure how yours works, but on some "remote-only" devices you can use a (potentially sketchy) USB split cable with power connector and an additional USB port for a keyboard / keyboard-mouse combo so you can use a regular browser to download and install apps.