EmuDeck isn't letting you auto install Yuzu anymore...

But it does install Ryujinx for you.

But it doesn't provide BIOS or prod/title keys, gotta find those on your own.

There's also Citron, but EmuDeck just lets you know it exists and won't auto dl it.

Ryujinx has a flatpak (though its a fork) in the base Discover store on a Deck running SteamOS, so its just on mainline flathub.

Yuzu and Citron appear to no longer be on flathub.