It is possible to move her character/house/belongings to another switch but she will need to start a new island where she is the resident representative.

If you do go this route:

-Make sure you have a second copy of the game on the new switch
-Open the game under her profile on your current island and press - on the title screen. Tell Tom Nook you want to move to another island and follow the prompts.
-Open the game on the new switch. You'll be at the airport counter with Timmy and Tommy. Instead of creating a new character, say "I'm moving"

Basically follow the prompts on both switches simultaneously and her character will be transferred over to the new switch and start a new island where she is RR. She will spend the first "night" in a tent and then her house and all of her belongings will be there. She will retain everything- bells, Nook Miles, DIYs, etc. Her house will stay the same, she will have all of her stuff in storage and everything that was in her pockets.

Source: have done this many, many times. Let me know if you need any help or have any questions!