POST : https://www.kapadiya.net/wordpress/woocommerce-paypal-for-inr/

function.php

function woocommerce_paypal_args_for_inr($paypal_args){
    if ( $paypal_args['currency_code'] == 'currency_code'){
 
        $convert_rate = currency_rate;  // $1 = how much
 
        $count = 1;
        while( isset($paypal_args['amount_' . $count]) ){
            $paypal_args['amount_' . $count] = round( $paypal_args['amount_' . $count] / $convert_rate, 2);
            $count++;
        }
        if (isset($paypal_args['tax_cart'])) {
            $paypal_args['tax_cart'] = round($paypal_args['tax_cart'] / $convert_rate, 2);
        }

        if (isset($paypal_args['shipping_1'])) {
            $paypal_args['shipping_1'] = round($paypal_args['shipping_1'] / $convert_rate, 2);
        }
    }
    return $paypal_args;
}

add_filter('woocommerce_paypal_args', 'woocommerce_paypal_args_for_inr');