TradeGecko's Payment Method is mapped with Shopify's Payment Gateway. It is not case-sensitive, and dashes/underscores will be replaced by spaces for matching. For example, if the Payment Method in TradeGecko is "Credit Card", a Payment Gateway of "credit-card" or "credit card" or "Credit Card" would still match.
First, you need to know the Payment Gateway Names in Shopify. To do this, login to Shopify Admin > Settings > Payment Providers. See below.
Second, make sure the Shopify Payment Gateway names exist in TradeGecko. If not, you have to create this Payment Method in order for us to capture the Payment Type. You can find this under TradeGecko Settings > Configuration > Payment Methods > New Payment Method.
And the Invoice will sync to XERO/QuickBooks with its Default Payment Ledger account.