2 loop clips can be used as over-layer with blending mode Add – Screen or multiply ( see the example of preview video) ....sound included. .
Film Strip Running
Alpha Channel: No, Looped Video: Yes, Frame Rate: 25, Resolution: 1920x1080, Video Encoding: H.264, File Size: 166mb, Number of Clips: 2, Total Clip(s) Length: 0:26, Individual Clip Lengths: 0:13, 0:13