Hi Chany,
The Text Domain of a theme and core plugin should be the same as it’s the standardness. Also, it’s a required requirement of Themeforest that the Text Domain will have to be the same.
If you want to translate the theme then you could use this plugin https://wordpress.org/plugins/loco-translate/
You could review the Loco Translate plugin Beginner’s guide, here https://localise.biz/wordpress/plugin/beginners
Best Regards,
ThemeLooks Support Team