This is very similar to a previous question, but they are not the same.
I am looking for assistance in finding the documentation for the TextureRenderTarget2D class so that I can access its buffer (i.e pixels) programatically. So far I have been unable to find a reference to the class on either the GitHub or the API documentation and would greatly appreciate a push in the right direction.
You can call GameThread_GetRenderTargetResource() to get the underlying FTextureRenderTargetResource object. Then you can use the RHILockTexture2D to get a pointer to the data. There are plenty of examples of that pattern in the source.
btw, the class in question is UTextureRenderTarget2D and is in TextureRenderTarget2D.h