Can we add Drop Down list to any Address Style attribute

Summary:

Under Address Style Format for Romania Country we want a drop down list for an attribute(SIRUTA CODE), In the Manage Address Format Screen we are unable to see any such option to add the drop down. We referred the Attribute Transformation but it would allow us to change the data type and many more activities however we can't add drop down values via transformation. Please let us know if there is any possibilities to add the Drop Down values to the attribute.

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