Have a DC launch in xone that can play games downloaded through xbox store and make a new DC controller to hook up with xone.
Im not sure how tech or emulators work but the OG Xbox was intended to play Dreamcast disc but the deal didn't go through.
I think the og xb was still capable of Sega CD games though through some sort of neogeo or maybe mod I'm not sure but there's a lot of info on it online.
Ms and Sega did team up to build the Dreamcast and Xbox is about the closest we had to Dreamcast 2. Sega even moved on to Xbox to make their exclusives including:
"Shenmue 2", "panzer dragoon orta", "Otogi 1&2"
Not sure if it's possible to update Xbox and make it read the license from old DC disc then download the classic DC game from xb store like how 360 emulator works. when inserting DC disc to Xone, a voice will promote up saying "this game is intended for Sega Dreamcast" so the Xbox knows
I heard DC disc were just basically CD ROMs and but more space and had terrible security anyone can pirate them so I think it's just a matter of Sega giving permission.