Please make sure you have read the Tag Syntax document and understand how tag attribute syntax works.
Gets a resource bundle and place it on the value stack. This allows the text tag to access messages from any bundle, and not just the bundle associated with the current action.
{% remote_file_content https://raw.githubusercontent.com/apache/struts/master/core/src/site/resources/tags/i18n-description.html %}
{% remote_file_content https://raw.githubusercontent.com/apache/struts/master/core/src/site/resources/tags/i18n-attributes.html %}
<s:i18n name="myCustomBundle"> The i18n value for key aaa.bbb.ccc in myCustomBundle is <s:property value="text('aaa.bbb.ccc')" /> </s:i18n>