I don't have to explan this, but in any case. Don't put any ext-config.ini inside the rss_formula_x_evo folder. It just goes to 'extension' folder (this folder will make changes for all the cars, and have priority over the livery folders), or it could also go to the livery folder you want (for example, \steamapps\common\assettocorsa\content\cars\rss_formula_hybrid_x_evo\skins\RB18_1)
Whatever the decision you take, be sure to put the .kn5 file with the ext_config.ini both are inside the add-on zip.
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