I’m Back Partners with Yashica

It would be fun if it actually works - there have been a few false starts in this area!  Two things immediately strike me: firstly, every digital back needs to be supplied with a generous number of sensor cleaning pads as dust is going to be a mega-problem!  Secondly, using the m4/3 format, the 2x crop factor is going to be great for standard to telephoto focal lengths but to get a wide-angle image using a C/Y camera you are going to have to buy Zeiss lenses such as the 15mm (start saving now) & 18mm or something similar to the Tamron SP 17mm f3.5.  Yashica's widest true wide-angle is the very rare ML 20mm and that will only render an image akin to that from a 40mm lens - barely a wide-angle.  On the positive side, you're always going to be shooting through a lens' sweet spot.

I hope it comes to market; if it works as intended and is robust enough to keep being taken in and out of film cameras, it could be fun.