Dear gents,
I can happily confirm that the Cable Matters adapter works flawlessly on the 2019 OLED55C9PLA model, plugged into a usb 2.0 port. LG decided to drop USB 3.0 but, even plugged into a USB 2.0 port, it performs better than the LAN port. With the network cable plugged into the LAN port, and a 40+ GB BluRay movie, i would get buffering every 2 seconds (using DLNA with the SmartShare app installed on my PC). Plugged in the adapter into a 2.0 port, "unknown device connected" and everything works! Netflix, Prime, updates, etc. I do not have wifi configured, it shows wired disconnected and wireless disconnected.