A very simple thingy that keeps the Switch 2 JoyCon straps together when not attached to the JoyCons. The JoyCon straps fit in either orientation, you attach the same way you attach them to the JoyCons (i.e. hook the strap end on first) and you simply pull them apart from the none strap end to take them off.

Be sure to rotate the part 90 degrees to print from one of the flat faces. I printed them in PETG, at 0.2 layer height, 3 perimeters, 5 solid top, 4 solid bottom with 10% infil, this worked well for me as these are my default settings majority of the times, I'm sure you can tweak your settings slightly and it'll still work out fine.

EDIT - I've updated the model by adding a chamfer to the edges.