LWRP - Blend factors for Alpha are ignored?

Hello there! I'm trying to write a variation of the basic LWRP Universal 2D 'Sprite-Lit-Default' shader, that uses Multiply blending instead of the usual one. It seems this should be achievable just by tweaking the shader's blending properties.

So if I set the shader blend properties to:

Blend DstColor Zero

​

The colors are blended ok, but he alpha is not affected turning the rendering fully opaque:



So I would need to specify the blending for the alpha channel with something like:

Blend DstColor Zero, SrcAlpha Zero

​

However, specifying the alpha blending does nothing - I get the same opaque result, the alpha is not affected. Whatever combinations of values I might try (One One, Zero Zero, whatever ) has no effect.

So am I doing something wong (hopefully) or is this a quirk of the LWRP or, more specifically the 2D Universal rendering?

Thank you for your cooperation!