If you are willing to change currency symbol ($) to currency code then WP Travel plugin provides the feature regarding changing currency symbol to currency code using filter.

You can change currency symbol to currency code adding following given code(we have provided code for USD) in functions.php file of your child theme.

function customized_currency_names( $currency_symbols ) {
    $currency_symbols['USD'] = 'currency code';

    return $currency_symbols;
}
add_filter( 'wp_travel_currency_symbols', 'customized_currency_names' );

Also, you can change currency symbol to currency code for other currencies too by replacing currency symbol [‘USD’] with the currency symbol whose currency symbol need to be changed .

For detail assistance regarding creating child theme, please refer link.

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If you have any queries, please submit it to our contact page.