And when hitting the 'download with manager' button on an oldrim mod, NMM opens with the Oldrim version ONLY if you have the game installed, otherwise you get an error when NMM opens, saying you don't have the game present. And inside that the file structure is completely identical. What Vortex sees is nothing but a zip file with files BELOW 'Skyrim' or 'Skyrim Special Edition'. Inside a downloaded file there is NO INFORMATION WHATSOEVER which allows to distinguish between Skyrim and Skyrim SE. But especially older managers like NMM, and ESPECIALLY when you go to download from from sites like Loverslab (as he does) then there is no way even an intelligent mod manager like Vortex can check that. I'm not aware if Vortex makes checks when you say 'Download with manager' because I would never load incompatible mods. Looks like you did more things wrong than installing the wrong mods. In order for NMM to download Oldrim mods you need to have the Oldrim game installed as well. When using a mod manager like NMM you cannot download mods for Skyrim and install them on Skyrim SE because NMM cannot do that.

Skyrim zaz animation pack not working