Possibly. Skywind relies on SKSE and SkyUI so those mods need to be fully ported before we can seriously consider it. If so, it's likely as it has a noticeable frame rate increase when used with our assets. However the new Editor has got some new "quirks" which drive landscapers crazy, so we'll have to wait and see.
Skyblivion is likely in a similar boat, minus SkyUI.
you can COC between worldspaces but it wouldn't make much sense to include doorways between the realms as the time periods are so different. A quick mod to make though for those that desire it.
https://www.youtube.com/watch?v=J3b9pcgzZSk Here ay go. Loose REL date is March-April 2017