IR signal can balance off walls, if it were wifi signal which goes through walls it can't be pa I red to more then one Roku at a time. Your Hisense and Onn Roku tv' s remote emit different codes, but yge problem here is that the Hisense accepts both codes, where Onn only accepts one.
You could purchase a voice remote, which the wifi remote would be paired to the Onn Roku tv, so wifi remote will only control the Onn, and Hisense remote would only control the Hisense. You would have to abandon the Onn Ir remote for good.
Edmund
Roku Community Streaming Expert
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