My idea is to add that you can seen what you when you are recording, i mean when you are recording you take stuff, see you hearts etc, my idea is to add an update when you are editing you can go inside a player and set camera tilt and a modus to see when that players go to a chest/inventory you see his inventory to, you can also see his hearts and armorbar/foodbar. When its not possible for all players, is it possible to do it by only the guy that record replaymod?
I hope this will be added in the future.
When you have questions you can ask them.
Recording the GUI for all players is impossible, so that's never going to be added.
As for the recording player: While it would technically be possible, it would mostly work completely different from how everything else is recorded.
For those two reasons (it'll only work with a single player and it doesn't integrate with the current system at all) we decided that the ReplayMod will not support recording GUIs and for sake of consistency we outright disable any and all GUIs during rendering (even those that we theoretically can show like the scoreboard).
When you want to record what you see on screen, then what you want is a Screen Recorder (OBS is free, powerful and works great from what I've heard).
I'm not sure I addressed all of what you said because I don't quite understand what all this has to do with "Camera Tilt".