Look into Scotty Anderson’s technique. Scotty has developed a method for alternate picking double stops using the pick and nail of his index finger.
This technique mechanically resembles a DWPS deviation and flexion/extension based crosspicking movement, with a slightly modified hand position to allow the fingernail to strike the higher string almost exactly as the pick strikes the lower string.
I found the movement very awkward for a long time, but I’ve started to make some headway with the technique. There’s a bit of a knack to it, and my fingernail needs to be maintained at a particular length.
The technique is very versatile and Scotty has taken that basic concept to the extremes and devised more advanced variations, including triple-stop alternate picking and variations involving non-adjacent strings.
If you’d like, I can make a short video later demonstrating the basic principle, but be aware that I’m still at a very basic level with this technique.