I was thinking about this too. Maybe it could be an option in settings to switch them, or to split the lever in half. Don’t forget to vote for your own request ;)
I think the best way to implement this is to have two layers of the throttle. The bottom layer being so that they are synchronized and the top so that you can split them. Now we have to find ways of actually being able to do that and controlling the plane at the same time.
Nice request! :D
Hopefully this shows up one day once the devs figure out what to do on how to implement this.