To start off, Maria is alive and well in this 'verse.
Dr. Gerald Robotnik ran another gaming company. There were rumors and allegations that he was secretly up to something shady behind the scenes, but before any formal investigation could really get going, he up and died. Whoops.
The company was left to his grandchildren, but since Maria is only in middle school, Ivo's in charge of it now. The company still releases games, but not as many as it once did, and its main draw is the nostalgia factor to its already existing fans.
I'm sure Ivo will never happen upon Granddad's secret projects and decide to wreak havoc with them, that'd be silly
In the meantime, Shadow is more or less Maria's legal guardian/surrogate big brother, and they live in a pretty nice apartment within walking distance to Maria's school.
(Maria was pretty sickly when she was small, and her immune system still isn't all that great. So the light exercise is good for her.)
Still trying to decide what Shadow does other than fret over Maria. Either he acts as Ivo's oft-ignored voice of reason or he's taking university classes part-time.
I've already said that Maria and Amane are BFFs and play a pair of awesome treasure-hunting sky pirate princesses over in ls: d.
Question: Can the players actually be royalty in that game?
Answer: Shut up they are princesses because they said so and are you really going to try to tell them they can't be?
...what if Shadow was both, though?

b
I wanna retool Ris for it. ...also because I wanna just play with an AU for Ris that's closer to her usual personality anyway but y'know
I want to actually do something with my characters for it, yeah.

;
Shadow walks Maria at least partway to school each morning, though lately she's been meeting up with Amane at some point and going the rest of the way with her.
Both their big brothers worry regardless of how ridiculous the girls assure them they're being.
Also, a scene from a typical morning in Shadow and Maria's apartment...
Maria: /waving to the framed photo of Dr. Gerald in the main room/ Bye, Grandpa! You're in charge while we're gone!
Shadow: Try not to burn the place down, old man.
Maria: Shadow! That was one time, and that was years ago! Are you ever going to let that go?
Shadow: Nope.
omg... Shadow, please. Please