Add multiple flavors in Unity project

I have a completed Unity project and what I am trying to achieve, is to have multiple flavors of the project and only change text, backgrounds, sounds, etc. I know I can just copy the project and do the changes needed but in this way, every time I do an update I will have to do it on other project as well and this is just duplicate work. I am looking for something like Android flavors that I can just have separate folders for the files I want to change only. I already checked this link but didn’t help me.

Yes you can do this, they call it reskinning, I’d probably call it themes rather than flavours… You have to create a system for it, you could make a enum that has different themes:

enum Theme{ SCI-FI, MEDIEVAL, CARTOON}//whatever you want…

Then you have an object of type Theme:

Theme theme;

and you use that to select your theme. You then have to implement a system so that when you change the theme it switches all image and sound and whatever references with ones tagged with the theme.

Or you could have a theme SO class that has all the references to the images and things you want to change:

class Theme: ScriptableObject{
Sprite background;
Texture texture;

something like that…