You basically set the objects transparency to around 0.05 and use a glass material with a transparency of around 0.99. If you put the glass over the material, it’ll appear completely transparent!!
Yeah I first load the sword in a frame and use an alpha0 mask to hide a part of the sword. I also have a character mask and and I dynamically change sword viewports Z Index based on the camera distance between sword handle and the character which works 99% of the time. The only problem is when looking head on it disappears, but that might be fixable with a hollow mesh. There is also lighting change due to viewports being pretty stripped down, so thats where glass method is better.