A:Answer If you're looking to be able to play your save file on say the lite and then pick it up on the console Switch, I unfortunately believe that won't work. The island, the save file basically, in New Horizons is tied to the Switch system itself and you can only have one island per system. If this seems annoying, you're not alone in that belief. In the most recent update (the Aug. update) they added in the ability to backup your island to cloud storage if you have an online subscription so you can recover your island in the event of damage or a lost Switch. I'm not entirely sure if they put a limit on how many times you can download from the cloud or something, as I have not needed to use the feature, but when the game released they originally stated they didn't have cloud backup as they didn't want people to abuse it to manipulate mechanics in the game.
If you were curious about buying one digital copy and having two separate profiles use it, rather than one person jumping between the systems, I believe there are some articles online mentioning how to do that. However, with things such as that I would recommend attempting it at your own discretion, and due to the sheer amount of time you can put into this game I personally wouldn't do anything to risk losing progress.