Export and import data to an external accounting software

I have to make a link between SAGE accounting and B1 for a frnch customer.

I want to export sales and prurchase invoices to SAGE

and import customer and supplier payments.

I would like to know what would be the consequence in B1.

Ould it be "transparent" for the users ?

For example do I have to make the Year End Closing ?

Is there other things that I have to do except make the setiings as if I use the B1 accounting

Thanks for your help

Christophe FLAMENT