Bottom line up front: the channel buttons don't seem to work.
I've got 2021 Vizio TV and a Vizio soundbar. Both seemed to be added correctly...the remote controls the volume on my soundbar and the TV's power and Input buttons are working. I'd also note that when you +Add a Device, I just had to identify my TV as a Vizio--there was no selection for a specific model.
I noticed recently that the channel buttons, however, do not work for my TV. On the ONN's device setup for the TV, there's a submenu titled "Set Up Buttons" that covers 3 buttons (Input, Volume, and Power). I don't fully understand the point of that menu because all it seems to do is test and walk you through how to use those buttons. I validated that the Input and Power buttons work. But there is no option to test the channel rocker.
Do any of you guys actually have that channel rocker working on your TVs? Any further ideas how I might get that button(s) working for my Vizio? It's just really odd that the remote has those buttons at all (IMHO) but omits them from the settings.
The Channel Up/Down buttons are for APPs. For liveTV streaming from YouTubeTV, Sling, Pluto, Xumo, etc. Those buttons are not to control the TV's internal broadcast channels.