I tried it today and I can't transmute it.
The click boton stays gray... I did the same thing 1 month ago and It worked.
Got the same problem, on item transmutation, I put the hood on the right, and the boton was grey for 4/5 masks, and I tried to put it on the left, and it worked with the masks I tried before. Maybe it's not rellay the solution, but you can try it if it don't works.