Here’s a quick example I threw together, at least one way to go about attempting this method. Just really depends on what your final needs end up being.
In this image I have a hallway setup. The first part is the final results after backing the lighting.
This is using a stationary spot light with a pumped up value to push some light down the hallway.
For the backlighting purposes you won’t get that kind of look from a standard light as well. You’ll end up similar to your image above. However, if you use a plane and set a basic emissive material on it that multiplies its brightness (mine is only using a 1.5 multiply of a constant 1) you can get a nice even look for this backlit effect.
Lastly, select the skeletal mesh in the level and set the Indirect Lighting Cache Quality to 0. With Point or Volume it’ll use the volume samples for the indirect lighting cache to help give some bounce light to your character. For this, it’s not always needed or you don’t get the exact effect you want, so setting this to ILCQ OFF you only get direct lighting from the stationary light for the character mesh.
Keep in mind that if you use a higher multiplier for your emissive value you’ll get more bloom around your character. Use a post process volume and try adjusting the Bloom settings for the best results and tightening up some of the effect.
I hope this helps give you at least one way to look at doing this for you for you project. Keep in mind there are some other solutions that are likely to give you results as well, this is just one method I thought I’d add here to help you if it fits your needs.
Tim