Import Models Store in AX 2012 R3- With the Help of Power Shell:
The Import-AXModelStore cmdlet enables you to move metadata between environments by importing a model store from a file. You can either choose to import the new model store directly to the default schema (dbo), or you can import the model store to a different schema, and then apply it to the default schema.
If you import the new model store directly to the dbo schema, you are likely to incur greater downtime, because you must stop all Application Object Server (AOS) instances while the model store is being imported. If you import the model store file to a non-default schema, you may incur less downtime, because AOS instances can remain active throughout the import process. AOS instances must be stopped when the new model store is applied to the default schema, but this is a shorter process than import.
When you import a model store, you can back up the existing model store to another schema. If an element ID conflict occurs during import of an .axmodelstore file, the import will be stopped by default.
PS C:>Import-AXModelStore -File Staging.axmodelstore
PS C:>Import-AXModelStore -File Staging.axmodelstore -SchemaName TemporarySchema
PS C:>Import-AXModelStore -Apply:TemporarySchema
PS C:>Import-AXModelStore -File “D:UATaxBuild28-08-2017UAT.axmodelStore” -idconflict:overwrite