Where the merchant in Expensify is an exact match to a contact you have set up in Xero then exported credit card expenses will show the vendor name. If not we use the the default name Expensify Credit Card Misc. This is done to prevent multiple variations of the same contact (e.g. Starbucks and Starbucks #1234 as is often seen in credit card statements) being created in Xero.
To change merchant names to match your vendor list in Xero, we recommend using our Expense Rules feature. More information on this can be found here.