People can just design and print their own 
Specs:
- 27.5x3.0 @ 425cs
- 29x2.8 @ 445cs
- Works with 32t 52mm chain line and 34t 55mm chain line
- 8mm of tire clearance each side
Keep in mind I use worst-case tolerances. I don’t play the “some 2.8 will fit” or “will fit with sliders all the way back” games.
For 27.5x2.8, I think plate yoke on the DS can work well. Not as easy as a plug and play yoke though.