Hey Fabrice,
Set a Texture Sample as your EmissiveColor on your material and make sample your texture render target from SceneCapture2D. That should be it. Then you can just place your material on what you want to reflect keeping in mind you probably want to rotate and move your SceneCapture2D where material will be facing toward otherwise it would look like a Camera, which if you want it to be that you could. Keep in mind that these can weigh system down so you want to try and limit amount you have in one area.
Best Regards,
Ryan