Shopify's Order Export report displays the Created At and Paid At fields as the Orders and Transactions created_at field.  Similar to how Shopify's Order timeline works, the Order Export does not export the processed_at fields that were used to import the order and transaction date.  

The created_at field is a read-only field that is populated by Shopify and set to the date the order was created in Shopify's database.

This means, when exporting your Orders using Shopify's Order Export feature, the orders will have a Created At and Paid At value of the date the order was imported.  Since Shopify doesn't allow us to write to any created_at field, these two values will not match the dates you provided on import.

Possible Solutions

Since there is no way to change the Created At and Paid At fields on Shopify's Order Export, you'll need to install a 3rd Party app if you want to export your orders with the date used to import your orders.  In order to do this, you'll need to export the orders processed_at field and the transaction.processed_id field to have the correct import dates.

If you want to use our app, EZ Exporter, to export your Orders after they've been imported you can do so by using the "Shopify Default Format (Similar But Not Exact, Last 7 Days Orders)" template and changing the Created At and Paid At fields in the Calculated Fields section like below: