I Want To Make A Replay / Theater Mode Mod

as per the title, i am looking into making a demo recording mod for SHAR, and being somewhat new to modding I was hoping to get some much needed advice on how to go about it. I'll take all the help i can get. A few features I'm looking to create would be, freecam, timescale (idk if thats even possible), a way to edit dvars (again i dont even know what dvars there are in SHAR, or if this is possible), dollycam, an fov slider (hopefully there is an fov dvar), and this is probably really pushing it, but a way to render a depth map in game. I know this is probably a massive task but im more than willing to take it on, all i need is some advice on how to do it. thanks in advance for any help

Unless you're able to program in C++ and assembly, you're not going to be in luck. All major features like this require a lot of code. To this day, there are no community hacks and are all made by Lucas himself.