Bulk Change Custom Order Status wpadmin

add_filter( 'bulk_actions-edit-shop_order', 'misha_register_bulk_action' ); // edit-shop_order is the screen ID of the orders page

function misha_register_bulk_action( $bulk_actions ) {

	$bulk_actions[ 'mark_packed' ] = 'Change status to packed'; // <option value="mark_packed">Change status to packed</option>

	$bulk_actions[ 'mark_shipping' ] = 'Change status to shipping'; // <option value="mark_shipping">Change status to shipping</option>

	return $bulk_actions;

}

add_action( 'handle_bulk_actions-edit-shop_order', 'misha_bulk_process_custom_status', 20, 3 );

function misha_bulk_process_custom_status( $redirect, $doaction, $object_ids ) {

	if( 'mark_packed' === $doaction ) {

		// change status of every selected order

		foreach ( $object_ids as $order_id ) {

			$order = wc_get_order( $order_id );

			$order->update_status( 'wc-custom-packed' );

		}

		// do not forget to add query args to URL because we will show notices later

		$redirect = add_query_arg(

			array(

				'bulk_action' => 'marked_packed',

				'changed' => count( $object_ids ),

			),

			$redirect

		);

	}

	if( 'mark_shipping' === $doaction ) {

		// change status of every selected order

		foreach ( $object_ids as $order_id ) {

			$order = wc_get_order( $order_id );

			$order->update_status( 'wc-custom-shipping' );

		}

		// do not forget to add query args to URL because we will show notices later

		$redirect = add_query_arg(

			array(

				'bulk_action' => 'marked_shipping',

				'changed' => count( $object_ids ),

			),

			$redirect

		);

	}

	return $redirect;

}

add_action( 'admin_notices', 'misha_custom_order_status_notices' );

function misha_custom_order_status_notices() {

	if( 

		isset( $_REQUEST[ 'bulk_action' ] ) 

		&& 'marked_packed' == $_REQUEST[ 'bulk_action' ]

	 	&& isset( $_REQUEST[ 'changed' ] )

		&& $_REQUEST[ 'changed' ]

	) {

		// displaying the message

		printf(

			'<div id="message" class="updated notice is-dismissible"><p>' . _n( '%d order status changed.', '%d order statuses changed.', $_REQUEST[ 'changed' ] ) . '</p></div>',

			$_REQUEST[ 'changed' ]

		);

	}

	if( 

		isset( $_REQUEST[ 'bulk_action' ] ) 

		&& 'marked_shipping' == $_REQUEST[ 'bulk_action' ]

	 	&& isset( $_REQUEST[ 'changed' ] )

		&& $_REQUEST[ 'changed' ]

	) {

		// displaying the message

		printf(

			'<div id="message" class="updated notice is-dismissible"><p>' . _n( '%d order status changed.', '%d order statuses changed.', $_REQUEST[ 'changed' ] ) . '</p></div>',

			$_REQUEST[ 'changed' ]

		);

	}

}