A bunch of Ubisoft games can now be purchased from the Xbox PC app, most of the AC Series and Far Cry. This is to offer more games for the Xbox PC app as it starts targeting handhelds with their new console mode UI. More trainers should be made for these xbox version of the games.
I linked some Ubisoft game purchasable via the MS store for PC.
Shadows
Buy Assassin’s Creed Shadows | Xbox
Origins
Buy Assassin’s Creed Origins | Xbox
It seems like ms are expanded efforts onto PC now.