Zilverback offers integration services between Fortnox and the following:
Order transactions from your Shopify store can be transferred as invoices to Fortnox. Likewise, order payments can be transferred as invoice payments in Fortnox. Whether you have a card, Paypal or any other third-party payment gateway, the integration can handle it. Paypal charge, for example, will be reported as Write-Off in Fortnox.