The safest, easiest, and most rewarding way to play Firewatch is through official channels.

Keep an eye out for limited-run physical releases from reputable boutique distributors if you prefer owning a physical cartridge.

If you are looking for free content on the Nintendo Switch, you can find a dedicated section for "Free-to-Play" titles in the eShop: Nintendo eShop on your Switch. Search/Browse Price Range Scroll to the bottom to find the category and select Titles like Rocket League are available here for Free Download on Firewatch or recommendations for free-to-play games with a similar vibe?