If you are curious about a replacement for AccountEdge for Catalina, you are not alone. As the link below indicates, "AccountEdge is not and will not be Catalina-compliant".
This solution provides a few questions to ask yourself to determine if Big Business might be suitable replacement. (6993)
If you are running AccountEdge and looking at Big Business as a replacement, the main question to ask yourself is whether your business is mostly inventory or mostly service.
Big Business is inventory-centric and past converts from AccountEdge habe been looking for easy or easier ways to handle large inventories, likes tens of thousands of products, or more than one warehouse, or kits in countless combinations.