Hello,
Please check the Loco transaltion of this plugin, our theme does not influence the payment plugin.
Here is a video tutorial that should help you translate your website texts with a Loco Translate plugin https://www.youtube.com/watch?v=D3NsDdMzsls&list=PLMw6W4rAaOgKKv0oexGHzpWBg1imvrval&index=3
Please check the video tutorial to see how to save the translation file correctly. You can remove the plugin and translations would remain. Also, translations would remain after each theme update.
To translate the WooCommerce strings or other plugin strings, you need to create a separate translation in Loco > Plugins > WooCommerce in the same way as shown in the video.
Best Regards