You can only do that by using simlinks. There is no option in the game to do that.

I read that, but I don't want to save the entire program in a different folder, just the games. Now, in Windows, they're saved in %USERNAME%\My Games\0ad I only want to save only the games in G:\0ad and I don't understand where I can do that.

I think a major thing the current Han in the game lack are proper headgear models, for the minister, heroes, etc. Also, as you indicate, some of the weapon models can be improved, and lastly a larger variety of accurate body textures could be employed.                 

How can I set the folder where I save my games? I play the latest version of 0AD on both Linux and Windows 11 and would like to be able to decide where to save the files, if possible.