Validate the value of a tag based on the values of objects located in several other xml files using XSD schema

I want to validate that the value of a tag in xml coincides with the values of the tags of other objects located in different files using XML Schema.

Take that I have several Scripts.xml files like this:

Script1.json

<script>
  <scriptname>script1</scriptname>
  <type>script</type>
</script>

Script2.json

<script>
  <scriptname>script2</scriptname>
  <type>script</type>
</script>

These files have a schema like this

<?xml version="1.0"?>

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="script">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="scriptname" type="xs:string"/> 
                <xs:element name="type" type="xs:string"/> 
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>

Then I have another file called UseScript.xml

<use_script>
  <script>script1</script>
</use_script>

with schema

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="use_script">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="script" type="xs:string"/> 
            </xs:sequence>
        </xs:complexType>
    </xs:element>
</xs:schema>

What I look is that the validator search all the xml files in a folder with type "script" and then compare it with the value of field "script" in UseScript.xml.

How can I reference the scriptname from the script1.xml in the schema?
Is it possible at all?

XSD can't do validation across multiple files. That's true even with XSD 1.1 assertions, though you might be able to do it using vendor extensions.

One workaround is to combine all your XML into a single file prior to validation. You could do this using an XSLT transformation, and if you have a schema-aware XSLT processor, you could actually validate the transformation result from within the XSLT code itself so it becomes a single-step operation.

The other solution is to use a different technology for the validation. I'm not sure Schematron or RelaxNG can handle it either (someone might correct me). But don't overlook the possibility of doing the validation directly in XSLT or XQuery.