I use a Skull & Co grip for the original Nintendo Switch, it has its own case but its huge and I wanted something more travel-friendly.
This solution uses rubber bands (I used hair rubber bands) to attach to the switch and it protects the screen and the joypads.
One side it's a bit difficult to push the rubber band in (so it will stay there) but the other has more spacing to make it easier.
The openscad source is available if you want to make changes (the code is a bit of a mess, sorry).
Print with the flat part of the model at the bottom (flip it in your slicer).
The author marked this model as their own original creation.