If I change/edit customer's shipping address, will it get reflected on previous invoices?

Yes! If you edit customers existing shipping address, the changes will get reflected on the previous invoices.

To do so please follow the below steps:

Click on the added customer >> Shipping address>> Edit>> Make necessary changes>> Save and Update.

You can search for invoices created for the paricular customer in the search bar and view any previously created invoices to view changes.