I need different flag for languages.
It is possible to use your own images as flags. You have to use PNG or JPG files and name them with the WordPress locale. For example, en_GB.png. Then upload this file in the /wp-content/polylang/ directory (create the directory if it does not exist). Don’t use the /polylang/flags/ directory as your file would be removed when automatically updating the plugin.
Once the custom flag is uploaded, go in Languages > Settings > URL modifications module then click on save changes. Note that your custom flags are not used on admin side.
I did all of this but the language switcher have the same flags... I don't see how the plugin would recognize that if I place an en_GB.png file in its directory (Not the flags folder). Feels like they miss something important, how to assign the images to certain language...