I couldn’t get my USB 3 splitters or ethernet working at first on my new 2023 Onn box but eventually I figured out how get them working. I noticed others were also having USB and dongle issues. This is what I did.
Turned off wifi. Got into developer options scrolled down to “select USB configuration” switched it from “charging” to “RNDS (USB Ethernet)” then went back and hit restart. When it powered back on with my OTG dongle connected with my USB 3 splitter with Ethernet I now I had an ethernet connection and my USB keyboard also worked. I know it’s slower but I’ve always found even at micro USB speeds Ethernet is a more solid and more reliable of a connection than a faster Wi-Fi connection on streamers. I had noticed a lot of people having trouble with USB. That’s what I did to get it working for me. In developer options at switchback to back to “charging” but after I restarted it back up several times now it is still working just fine. There’s a few other options under the USB setting in developer options to play with as well. Just remember anything you changed and developer options you may want to change it back so remember what you did. If nobody else had that issue maybe it was just a fluke for me. Good luck