It was pointed out to me that Pushbullet is much faster for file transfers. Made a quick demo https://youtu.be/aHEPEuqUsm8 - does not always work for me and max 25 MB file size.
Found the AirDroid app, which can transfer files directly to the Android TV from my Android Tablet, where I create the backup apks. No need for a go-between (cloud or usb) https://youtu.be/ddtK6IMLINQ
Found Air-Share for file transfers and its Air-Launch, which can sideload directly from an Android device to an Android TV. https://youtu.be/B2c_v1leeT4
