How to Move Payments on WooCommerce Checkout | https://www.ibenic.com/move-payments-woocommerce-checkout

functions-2.php

<?php
/**
 * Adding the payment fragment to the WC order review AJAX response
 */
add_filter( 'woocommerce_update_order_review_fragments', 'my_custom_payment_fragment' );

/**
 * Adding our payment gateways to the fragment #checkout_payments so that this HTML is replaced with the updated one.
 */
function my_custom_payment_fragment( $fragments ) {
	ob_start();

	my_custom_display_payments();

	$html = ob_get_clean();

	$fragments['#checkout_payments'] = $html;

	return $fragments;
}

functions.php

<?php

/**
 * Moving the payments
 */
add_action( 'woocommerce_checkout_shipping', 'my_custom_display_payments', 20 );

/**
 * Displaying the Payment Gateways 
 */
function my_custom_display_payments() {
  if ( WC()->cart->needs_payment() ) {
    $available_gateways = WC()->payment_gateways()->get_available_payment_gateways();
    WC()->payment_gateways()->set_current_gateway( $available_gateways );
  } else {
    $available_gateways = array();
  }
  ?>
  <div id="checkout_payments">
    <h3><?php esc_html_e( 'Billing', 'woocommerce' ); ?></h3>
    <?php if ( WC()->cart->needs_payment() ) : ?>
    <ul class="wc_payment_methods payment_methods methods">
    <?php
    if ( ! empty( $available_gateways ) ) {
      foreach ( $available_gateways as $gateway ) {
        wc_get_template( 'checkout/payment-method.php', array( 'gateway' => $gateway ) );
      }
    } else {
      echo '<li class="woocommerce-notice woocommerce-notice--info woocommerce-info">' . apply_filters( 'woocommerce_no_available_payment_methods_message', WC()->customer->get_billing_country() ? esc_html__( 'Sorry, it seems that there are no available payment methods for your state. Please contact us if you require assistance or wish to make alternate arrangements.', 'woocommerce' ) : esc_html__( 'Please fill in your details above to see available payment methods.', 'woocommerce' ) ) . '</li>'; // @codingStandardsIgnoreLine
    }
    ?>
    </ul>
  <?php endif; ?>
  </div>
<?php
}

payment.php

<?php
/**
 * Checkout Payment Section
 *
 * This template can be overridden by copying it to yourtheme/woocommerce/checkout/payment.php.
 *
 * HOWEVER, on occasion WooCommerce will need to update template files and you
 * (the theme developer) will need to copy the new files to your theme to
 * maintain compatibility. We try to do this as little as possible, but it does
 * happen. When this occurs the version of the template file will be bumped and
 * the readme will list any important changes.
 *
 * @see     https://docs.woocommerce.com/document/template-structure/
 * @package WooCommerce/Templates
 * @version 3.5.3
 */

defined( 'ABSPATH' ) || exit;

if ( ! is_ajax() ) {
	do_action( 'woocommerce_review_order_before_payment' );
}
?>
	<div id="payment" class="woocommerce-checkout-payment">
		<div class="form-row place-order">
			<noscript>
				<?php
				/* translators: $1 and $2 opening and closing emphasis tags respectively */
				printf( esc_html__( 'Since your browser does not support JavaScript, or it is disabled, please ensure you click the %1$sUpdate Totals%2$s button before placing your order. You may be charged more than the amount stated above if you fail to do so.', 'woocommerce' ), '<em>', '</em>' );
				?>
				<br/><button type="submit" class="button alt" name="woocommerce_checkout_update_totals" value="<?php esc_attr_e( 'Update totals', 'woocommerce' ); ?>"><?php esc_html_e( 'Update totals', 'woocommerce' ); ?></button>
			</noscript>

			<?php wc_get_template( 'checkout/terms.php' ); ?>

			<?php do_action( 'woocommerce_review_order_before_submit' ); ?>

			<?php echo apply_filters( 'woocommerce_order_button_html', '<button type="submit" class="button alt" name="woocommerce_checkout_place_order" id="place_order" value="' . esc_attr( $order_button_text ) . '" data-value="' . esc_attr( $order_button_text ) . '">' . esc_html( $order_button_text ) . '</button>' ); // @codingStandardsIgnoreLine ?>

			<?php do_action( 'woocommerce_review_order_after_submit' ); ?>

			<?php wp_nonce_field( 'woocommerce-process_checkout', 'woocommerce-process-checkout-nonce' ); ?>
		</div>
	</div>
<?php
if ( ! is_ajax() ) {
	do_action( 'woocommerce_review_order_after_payment' );
}

plugin.php

<?php
/**
 * Fitlering the template for Payment
 */
add_filter( 'wc_get_template', 'my_custom_payment_template', 20, 2 );

function my_custom_payment_template( $template, $template_name ) {
  if ( 'checkout/payment.php' !== $template_name ) {
    return $template;
  }
  
  return plugin_dir_path( MY_PLUGIN_FILE ) . 'templates/' . $template_name;
}