I've found this https://github.com/Codeusa/Borderless-Gaming/releases http://store.steampowered.com/app/388080 Might use it for some games with no support or have issues with vsync and such.
You do realize that program is basically just an AHK script, of which you can find very easily if you browse for 5 minutes.
It would be more useful to do the reverse. Exclusive fullscreen for games that only support borderless
GeDoSaTo can go both ways, but it doesn't work with everything. I'm not 100% on the limitations but I believe it still does not support x64 or DX11.
x64 is supported, anything besides D3D9 though is still not compatible. In addition to CodeUSA's utility there's also this: https://steamcommunity.com/groups/WindowedBorderlessGaming Not all games can easily be forced from fullscreen or windowed to borderless and these two software utilities can be useful for different games. (IE something that isn't entirely compatible with Borderless Gaming might work better with WBG.)