According to Official Guinness Records,
A book is typically translated and sold into other territories after proving to be a success in its domestic market, but the debut novel translated into the most languages prior to publication is Half Bad by Sally Green (UK), which had been sold in 45 languages in the year running up to its UK launch by Penguin on 3 March 2014.
For a complete list of 2014 records, please visit 2014 Guinness Records in United Kingdom.