You could put your colors into variables and "handcraft" your config file once.
Here is my example

Hello @danielporto 👋

There's no theming system. @Artem-Schander's way is interesting though. I'll give it five minutes.
If I update my configuration in this direction, I would go with

tmux_conf_theme_color_1='#ffffff'
tmux_conf_theme_color_2='#ff0000'
...

Because I think I won't survive reading tmux_conf_theme_color_black='#ffffff' 😅

Thanks @Artem-Schander for chiming in!

I've many refactorings ongoing so I won't rush this one for the moment

Touching on this issue, I would like to ask if there is any support for loading colors from Xresources. Much of my theming automation workflow is based on utilities exporting themes to Xresources colors which are then parsed in the configuration files of each program I need to theme. I believe it would be a nice feature.

I think this would be a great addition! For example, supporting something like this:

https://github.com/egel/tmux-gruvbox/

You could put your colors into variables and "handcraft" your config file once.
Here is my example

The best solution finded, I've added gruvbox colorscheme in no time, thanks a lot