I'm using mouse and keyboard on my series x and it constantly tells me that I need a controller to play. I found a work around, but seems weird all the same. Not sure if it's an issue on Microsoft's end or yours.
Also, not sure if it's a bug or an intentional feature but the drag and drop feature with keyboard and mouse doesn't work. Also can't use backspace or delete while typing quantity in crafting or searching in crafting.
Other than that I'm pleasantly surprised with how smooth it runs and can't wait for random Gen and mods