In Teiid Connection importer, it lacks a way to define the "import" properties that makes usage cumbersome for user to define to import specific parts of schema, or sometimes impossible (see TEIID-1905)

basically, when user chooses the "translator", after they should be able define some custom key/value pairs as properties, when then should be converted as model import properties in "importVDB-vdb.xml" file. Some sample properties are defined here
https://docs.jboss.org/author/display/TEIID/JDBC+Translator

see "importer" properties. Do not confuse similar "execution properties" which are translator overrides. The sample vdb is like this

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<vdb name="hive" version="1">
  <description>Shows how to query HiveVDB using Hive</description>
  <property name="UseConnectorMetadata" value="cached"/>
  <model name="hive">
    <property name="importer.trimColumnNames" value="true"/>
    <source name="Hive conector" translator-name="hive" connection-jndi-name="java:/hive-ds"/>
  </model>
</vdb>

As per GUI concerned it should be added in "Select the translator and target model" panel, after the selection of translator