Seems like there’s a bug when stacking those two infusion together.
The “stack” itself works well. When I have both I see the cosmic effect, but dyed white from the Winter’s Heart.
Problem is when others see me. If the viewer get really close to me, the white effect disappear, leaving only the red cosmic one. Also said effect disappear based on the camera angle/position of the viewer.
My main guess is that is something related to the camera distance from the character with the infusion. If you’re too close, then it doesn’t show.