Here is how PayPal Express Checkout works:
- you add some products to the bag
- click "Checkout with PayPal"
- Ecwid redirects you to the PayPal site
- you sign in with the PayPal account or create a new one
- PayPal redirects you back to Ecwid
- Ecwid creates a new guest profile based on information from PayPal and shows the last checkout page
- you review your order, change the shipping method if necessary and press "Submit order" button. At this stage Ecwid recieves the complete address and calculates real taxes.
- Ecwid sends request to PayPal in background, PayPal charges your credit card. At this stage the correct tax amount is included into the payment.
In your shop you have a tax set up for Virginia shipping address. There is no tax for North Carolina in your setup. Hence if customer checks out with NC based shipping address, there will be no tax, and if Virginia based address is in action, there will be tax.
Your customers might see an estimated tax on the shopping bag page, but as soon as the get back to the shop from PayPal, they will see a correct tax according to your shop setup.