I am so lost and confused that it’s not even funny.
How the *bleep* do you get transparency/alphas working on clothes meshes~!

Okay, CmarNYC is a goddess we should all bow down before:
In TSRW, you need to export your project as a package: Edit / Project Contents, then Export.
Use Toolkit / Package Tools / Name Those Files to open the package and save a new version with all the files inside named.
Get S3PE and open the .package with it. Find the lod1 mesh (lod1 is the same as TSRW high detail), right click it and export to a file.
Use SimGeomEditor on the exported simgeom mesh file.
Back in s3pe, right-click the mesh again and choose Replace, and select the modified simgeom.
Save the package and use in your game.
This kind of has to be your last step, and if you have to make changes in TSRW you’ll have to export the package and replace the mesh again.
All is suddenly right in my world–time for a soda break!