There are different types of night mode. For me, it means a red overlay, but a google search reveals other options from a yellow overlay to just reducing screen brightness or contrast. Do you have an example of what you're aiming for?
I experimented with yellow overlays (as per your post - I didn't note that in my earlier reply) on midtones and highlights using luminosity masking. I tried wholly or partially desaturating and applying yellow overlays using 'overlay' or 'soft light' blend modes. But there's not much colour in the starting image to begin with, so whatever I did it looked yellow-ish all over.