I suspect that this will not be possible. Manager is written to work in every country in the world, so has to be somewhat generic so as to be usable in each country. It would be an impossible task for the developers to implement for each specific country’s specific requirements other than basic things such as default VAT rate and date format etc.
I believe that Manager does have the functionality to allow API’s so you can create some kind of interface, but don’t ask me how it works as thats outside of my expertise. But this is probably what you are looking for.
Have a look here - Api Integration for Manager