Hi,
This is great news, and you should definitely be looking at the new ArcGIS Runtime SDK for .NET rather than the existing ArcGIS Runtime SDK for WPF.
Regarding your questions:
1. Can I use ArcGIS Runtime sdks to build a non-cloud / non - server WPF Solution.
Yes, you can use the ArcGIS Runtime SDKs to build solutions which are not dependent on services and instead use offline/local data. This data always has to be created/authored somewhere though... which may require a desktop or server task initially. It would be worthwhile clarifying your editing workflow, since this may introduce the requirement for a feature service somewhere in the solution too.
2. Is the projection capabilities in Arcgis runtime comparable to engine, as engine has access to arcobjects.
There are projection capabilities in the ArcGIS Runtime via the GeometryEngine class, and we will be adding functionality for additional transformation options. The ArcGIS Runtime is not built on ArcObjects and therefore is not yet directly comparable, but over the next couple of releases it will become almost equivalent for most use cases.
Cheers
Mike