I'm just putting this here for anyone like me who has a bit of a stupid and can't initially get MO migration/import to work: When I initially opened up Vortex, the importer would go through all the steps fine, but the list would be blank and no actual migration would occur. I simply accepted the lack of this feature and began recreating my STEP list for Oldrim. After downloading a few things to test how Vortex's deployment feature works with mod removal, I, on a whim, decided to try MO migration again. Lo, and behold, it's working, doing the import as I type this! I have not tested for MO2 import yet, but it seems to me from early results that if nothing shows up in the import setup list, try downloading something for that game and running the import again.