You can find official and custom cover art for the US version of the game from these community resources:

Glossy is preferred to match the reflective nature of official inserts. 2. Required Dimensions

80lb (150g) glossy brochure paper or high-quality glossy photo paper .

HP heavyweight project paper is also a popular choice for a professional, non-flimsy feel.

The standard dimensions for a Nintendo Switch game cover inlay are: 208mm x 161mm (approx. 8.2" x 6.3"). Spine Width: 9mm to 10mm .

For the most authentic look, use paper that mimics the sheen and weight of retail game covers:

To produce a physical paper cover for (likely a digital NSP file you want to store in a physical case), you will need to print high-resolution artwork using specific paper and dimensions to match official Nintendo Switch releases. 1. Paper Specifications

At least 300 DPI to ensure text and logos remain sharp when printed. 3. Finding Artwork