X as in to exchange. Xchange, right? So it becomes Video Transmission Exchange. "Exchange" is a place where things are being passing back and forth or helped to pass back and forth. Take for example a telephone exchange. "A telephone exchange is called an "exchange" because it acts as a central point where different telephone lines are switched or interconnected, allowing calls to be routed between them. It's analogous to an intersection on a road network where vehicles switch from one road to another to reach their destination. " Google AI]. "Currency Exchanges" leverage the same meaning.