I'm not sure what you mean about per channel, but I'll try and expound further. I have all my sources going into a Marantz AVR, and the video out from the AVR going into the tv. If I switch to my Xbox One, the tv automatically switches to the "Game" preset (which turns off all processing for reduced input lag/latency for gaming). If I switch to my Apple TV, the TV switches automatically to "Home Cinema (User)" preset. It's called "(User)" because I went in and tweaked a bunch of settings. Like I said in the previous post, every once in a while when I'm watching something via the ATV, I'll just grab the tv remote and "just take a peek'' at another tv preset that is default, and I can't stand it. Fortunately, my fiance', who loves the look of motion blur but doesn't like it for sports, says, "You leave it however you like it; I'm fine either way and just wanna watch football without the runners' legs being smeared."
Edit: One thing the Samsung has over the LG is ALLM (Auto Low Latency Mode), which only matters if you're a gamer. In short, the Xbox One X has been updated to send an ALLM signal to the tv so that it will automatically switch to Game or another mode, depending on whether or not you're playing a game or, say, using Netflix on the Xbox. I use my Xbox to game and my ATV for pretty much everything else, so this hasn't been an issue for me. Just thought I'd point it out in case you or anyone else came across this thread who needed to know.