One of you bought a Switch, one of you bought an Xbox
It is the most common mixed-console pairing in a household, because the two machines do not compete - a Switch is what someone buys for Mario and handheld play, an Xbox is what someone buys for everything else. Then you want to play together, and you discover that the two libraries barely overlap.
They overlap more than you think, but not where you would expect. Almost nothing Nintendo publishes will ever appear on Xbox, so Mario Kart, Smash and Mario Party are permanently off the table. What does bridge the two is the third-party crossplay catalog - and it happens to include some of the best group games ever made, starting with one that Microsoft itself owns.
Minecraft is the answer, and it is not close
Minecraft is the strongest Switch-to-Xbox pick on this page for three reasons. It runs the Bedrock edition on both platforms, so the two of you are literally in the same version of the game. It supports four-player split-screen on the Xbox side, so a couch group and a Switch player can be in one world together. And it is a Microsoft game, which means it is on Game Pass and the Xbox player may already own it.
The one thing to get right is which Minecraft you buy. The Java edition that PC players often mean does not crossplay with anything on a console. Buy the console version on both machines. Our Minecraft review covers the trap in detail, because it is the most expensive misunderstanding in this whole category.
The free tier does most of the work
After Minecraft, the strongest Switch-to-Xbox games are free, which makes this pairing unusually cheap to solve. Fortnite has full crossplay everywhere and both of you almost certainly already have an account. Rocket League is five-minute car football with full crossplay and it scaled all the way down to Switch, which tells you how gently it runs. Fall Guys is the low-stakes option where nobody needs to be good.
Among Us is free on phones and a couple of dollars on consoles, with full crossplay, and it scales from four players to fifteen - so it also covers the evening when three more friends turn up. The full free list is on our free games hub.
The paid picks worth the money
Overcooked! All You Can Eat is the best paid pick for this pairing: both Overcooked games remastered with full crossplay across every platform, local and online. Human: Fall Flat costs less than lunch, takes eight players and crossplays. Moving Out 2 is the same energy as Overcooked with more forgiving assist options. Terraria is the deep one - eight-player sandbox co-op, cheap, with crossplay across most platforms provided both of you are on the same version.
Dead by Daylight is the outlier and the one to check the price on directly rather than through Amazon: four survivors against one player-controlled killer, full crossplay, and it needs exactly five people to be at its best.