I love that you're looking to include the most accurate information on your sales forms such as Invoices. Ensuring that the Shipping details are included is an easy task with QuickBooks Online, so let me give you a hand with that.
The first step is to ensure that your customers all have a Shippingaddress saved within their customer profile. To do this, navigate to the Customers tab within the Sales menu. Locate and select the customer you'd like to edit, and hit Edit at the top to make changes. Within the Address section, you'll want to ensure that the box for Same as billing address is unchecked, then proceed to enter the correct Billing and Shipping addresses. Make sure to hit Save when you're finished. You can learn more in this article: Enter the shipping address on all invoices.
Once that step is completed, you'll want to check off the Shipping field so that it's included on your Invoice. Here's how:
Navigate to the Gear icon.
Choose Custom form styles.
Find the style you're using for your Invoices and hit Edit from the Action column.
Choose the Content tab at the top.
Select the Header section within the template.
Scroll down on the left until you see the Display section.
Check off the box for Shipping.
Hit Done.
Now, so long as you've saved a Shipping address to your customer's profile, it'll populate on the invoices that you send them.