Change billing fullname with a custom field in Woocommerce emails

I using Checkout Field Editor for WooCommerce to make 25 custom field. I have problem billing_fullname not show in customer details but show in billing address. So i have thinking about a solution that i create another Name custom field.

I will hide my Name custom field using css in the frontend but i wondering how can i copy value in the billing_fullname into my custom field billing_name in the backend

Beside how can i hide billing details in Emails

I try remove some code in admin-new-order.php But when remove customer details remove too

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