Resident Evil 7 players with a Windows Store version of the game will be able to transfer saves between it and the Xbox One version, Capcom confirmed to IGN. The story was originally reported by Japanese gaming site Dengeki, which says the game on PC will also support a 4K resolution.
Cross-saves in this manner are present in games like Gears of War 4, Forza Horizon 3, and ReCore, which are all part of Microsoft's Play Anywhere promotion. That means if you buy a digital copy of one of these games on either PC or Xbox One, you'll get a copy of it on the other platform for free. While the three aforementioned games are first-party titles for the Xbox One, third-party games like We Happy Few, Cuphead, and Slime Rancher are confirmed for the program as well.
However, Resident Evil 7 is not confirmed as a Play Anywhere game, but I've contacted both Capcom and Microsoft for further comment and will update this article as I hear back.