Video tutorial: https://www.youtube.com/watch?v=cP72yAIsrEY

First method: HLAE streams and compositing

1. Record a clip on the original map (2viewmodelALPHA; 3particlesALPHA; 4playersALPHA; camera streams should be enabled)
2. Open your take folder and copy paste cam_main.cam file to the game folder ...\Counter-Strike Global Offensive
3. Join any demo that has a custom version of the original map
4. Type in mirv_camio import start cam_main.cam in the console to import the camera data
5. Enable 5world stream and record a clip with the same fps you recorded the first clip in
   Once recording is finished quit the game or type mirv_camio import end to stop importing the camera data
6. Import all the recorded layers in AE in the following order: 2viewmodelALPHA; 3particlesALPHA; 4playersALPHA; 5world
7. Remove gray outline on 2viewmodelALPHA and 4playersALPHA using Simple Chocker effect
8. Adjust colors on 2viewmodelALPHA; 3particlesALPHA; 4playersALPHA using Lumetri Color/Levels/Hue/sat etc.

Second method: fake demo with bot_mimic

Watch the guide and make your own demo on any map you like: https://www.youtube.com/watch?v=gs2vUx8G0-U