Nuke is perfect step. Ue4 compositing but very limited.
Ue4 Compositing Limit:
İmport .Exr Photo color is correct !!!
Light is terrible because ambient light and skylight doesnt true work !!
Click Play button and see changes, viewport doesnt see anything very important

İf solve this problems, After 3d compositing. 2D video convert to 3D mesh and any changes and working 3D area . İf 2d video moving object convert to 3d moving mesh is work its wonderful !!! This step is 3d industry changes!!!