In Astah Professional, you can set an alias for models. For example, you can name the model in English and Japanese and switch it accordingly. This is very useful, especially for offshore development.
You can let each model have 2 aliases. In order to add second alias, you will need to filter the alias pane.
Currently, you can add the alias to the following models:
Model, Package, SubSystem, Class, Attribute, Operation, Parameter, Template Parameter, Association, Association End, Qualifier, Generalization, Usage, Realization, Dependency, InstanceSpecification, Link, Link End, UseCase, Extend, Include, Extension Point, Entity, Domain, Primary Key, Other Key, External Entity, Data Store, Requirement, TestCase, Note, Text and diagram names.
If you do not need to use alias, you can hide [Alias] view which may increase performance.