This is not a modulate blend. Again, modulate blend takes color, and multiplies it over existing color. There is no specular or emissive. By the time it gets blended, it is just a color. By saying that giving you modulate blend on lit translucency would magically fix tinted glass for you, you are further confusing anyone, who might peek into the thread.
There are two practical ways to tackle the problem.
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Use Blend Add(Alpha composite) blending mode, and divide specular lighting by opacity. It works out of the box, needing only 3 lines of shader code to change. Breaks at low opacity values and instead of correct tint, gives you mix of background color and transmission color. Better than nothing, but still pretty terrible.
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Use Dual blend. That is what you are expecting, Specular lighting would be added and transmission(emissive, basecolor, w.e.) would be multiplied but there are performance and platform implications.
In both cases, distortion would still leave any objects with transmittance behind first one, undistorted.
So the essence of two pages here:
UE4 needs dual blend blending mode support added for lit and unlit translucency and separate translucency.
Until it is done, transmissive shading in UE4 will remain being triumph of raindance and workarounds.
TLDR: Use Scene Color Material Expression.