Frequent changes in application requirements demand not only schema and query adaptation but also migration and optimization of the object-relational mapping (ORM) code. While database and query migration are well-studied, application-level translation across ORM frameworks remains largely overlooked. We present ORMorpher, a unified and extensible framework for translating and optimizing across heterogeneous ORMs. Unlike existing solutions, ORMorpher supports both structural code transformation and resource-aware frame-work selection under user-defined constraints. Although broadly applicable, we demonstrate its effectiveness on three widely-used .NET frameworks: Entity Framework Core, NHibernate, and Dapper over Microsoft SQL Server, enabling practical, performance-driven migration. The source code is available at: https://github.com/milan252525/orm-convertor. A demonstration video is available at: https://youtu.be/zwGGdqXtrzM.