ASB's FastNet internet banking can export any account's transactions as CSV. The file needs reshaping before Xero or QuickBooks will import it cleanly; this page covers the export and the conversion, all done privately in your browser.
In FastNet, open the account, use the transactions or export area, pick your date range, and download as CSV. ASB exports sometimes include a few header lines above the column names describing the account and range; the converter skips unreadable rows automatically, and you can flip "First row" between Headers and Data if the preview looks off.
ASB files typically carry columns like Date, Unique Id, Tran Type, Payee, Memo and a single signed Amount. That maps neatly: Payee to Payee, Memo to Description, Tran Type or Unique Id to Reference if you want it kept. Dates are NZ day-first, so leave date reading on DD/MM.
If you reconcile in Xero, the Xero output's Payee and Description columns make bank rule matching much more reliable than a single mashed-together narrative, so keep both mapped.