I don’t think there is an NVME to micro SD card adapter that exists at the size needed, but even if you do find one, Unless you already have a very large Micro SD card on hand that you specifically want to use, I would just shoot for a used 256 or 512 SSD on ebay or a local marketplace app.

Now if you want a realllyyyyyy jank solution to use an additional micro sd card on it, you could always get a cheap USB C slim dock with a SD card slot and power delivery and tape it on the back.

Guys even if you hate microslop, this is not a bad thing to have the option for those who do use it. If it gets more people over to Linux I only see that as a good thing.

Your dock won’t work, as its most likely HDMI out only (not in). Even a lot of the capture cards that do have HDMI in tend to have a lot of delay, same with a lot apps that would encode a signal over USB, which would also have a performance hit on your Steamdeck as well. I unfortunately can’t think of a good solution except maybe upgrading your wifi access point and using a wired network connection with your Steamdeck, but by then you mind as well just buy an external USB-C display.

You can! They have replacement buttons for whichever layout you want for fairly cheap. I’m using the original ultimate Bluetooth with an Xbox layout.

Retrodeck in your case then if you just want a simple setup.