I would like to import a previously mixed stereo session into a blank ATMOS template and then rebuild the Mix in ATMOS without having to go back to rebuild every facet (reverbs, eq’s, compression, etc.).
I saw this done in PT during an ATMOS Tutorial. Is there a way to do the same thing in N11?
I don’t get the point…
add the needed Dolby-Atmos busses to your already existing project?
They suggested that was NOT the way to approach it in the Dolby Tutorial.
What’s wrong with Nuendo’s “Import Tracks from Project”-feature (…apart from the fact that it doesn’t import routings)?
I didn’t say there was anything wrong with it. I’m asking what’s the best way to do it, since I’ve never tried it before. Is that all that’s required, just “Import Tracks from Project?” All of my settings will still be there?
Yep, that’ll work just fine! In all of this time, I have never done that kind of import. I always went to the audio folder and imported 1 or 2 tracks for whatever reason. But any time I re-mixed a stereo project to a surround project, I used st10ss’ method of just adding the surround busses and re-routing the tracks from the existing project.
But ATMOS is a completely “New Beast!” With sooooo many complications just to set up the most basic routing, I wanted to be sure to follow the re-mix setup instructions to the letter. This option will work perfectly. Thanks Dietz! 
You’re welcome! 
All kudos to Steinberg for finally integrating this option.
Sidenote: As much as I love to mix in surround and 3D: Personally I think the ATMOS-hype is exaggerated, especially for music production. There’s no way to actually record in this format, and no way to integrate moving “Objects” to a proper music mix with all its intricacies like side-chaining FX, bus compression, mastering and the like. I prefer properly mixed AURO 3D for music which can be encoded to ATMOS in form of beds or static objects. This makes the routing less daunting, too. 
Kind regards,