Yes, the best solution I can think of is to have two players, and use SetViewTargetWithBlend to look through the first players eyes, which can be done in blueprint. See:
Some other questions that might be useful:
If you really want to have a single player and use render targets, the place to start looking is SceneCapture2D.
This allows you to read the pixels of a scene view in C++, but will get complex quickly. See also threaded rendering:
Thank you very much!
First, if i choose the two player solution, i just sync the player position and have two render targets with the same view on something?
Second SceneCapture2D: Yes, i really want to prevent something like that. I dont want to write my own render end solution.
(In Unity the only solution would be to write a native plugin and handle it myself, i really dont want this, for knowing reasons.)