I have found out a way to convert an item to Primal item. I have tried a few ones and they have been converted correctly but still use at your own risk.
Just unzip the file to the D3Edit folder and make sure files are replaced.
I modified the code based on D3Edit v1.0.5
I am still in the Newbie rank so I cannot post a link to the version, so please find it in author’s repo
You saved me tons of hours of rerolling with Kanai's Cube xD