Ps. By the way, I think stencil/silhouette luma is equivalent to the Mask Image by Brightness node. I should perhaps explore a bit more, maybe I can make it work here, too. Depends how it handles alpha, I guess.
Still, it would good to have these in the list of blend modes, it makes sense to those working across apps.
I'm trying to apply a circle mask to a list of images inside Build List. I have an image layer + Make Oval Layer. Closest thing I can find is Change Layer Blending, can't see a way to make it work. Closest I get uses multiply blend mode.
EDIT: solved this for my needs for now -- I was already using a list of images earlier in the chain, then converting to layers to make a grid. So I sent the images to a separate Build List to apply image masks, then sent them to be converted to layers.