Questions about Unitek Y-2140

It's just a cheap USB hub that can only do USB 2.0. A somewhat better USB 3 hub costs between 15 and 20 euros. on https://www.logitech.com/de-ch/products/webcams/brio-4k-hdr-webcam.960-001106.html#specs gives the hint: A USB 2 or USB 3 port (recording and streaming in 4K requires a USB 3.0 port and compatible third-party software).

79 cm and yes, USB sticks can be used without any problems