From http://www.w3schools.com (Copyright Refsnes Data)

XSLT <xsl:namespace-alias> Element

Definition and Usage

The <xsl:namespace-alias> element is used to replace a namespace in the style sheet to a different namespace in the output.

Note: <xsl:namespace-alias> is a top-level element, and must be a child node of <xsl:stylesheet> or <xsl:transform>.

<xsl:namespace-alias
stylesheet-prefix="prefix|#default"
result-prefix="prefix|"#default"/>

Attribute	Value	Description
stylesheet-prefix	prefix #default	Required. Specifies the namespace you wish to change
result-prefix	prefix #default	Required. Specifies the desired namespace for the output

The wxsl prefix is converted to the xsl prefix in the output:

<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:wxsl="http://www.w3schools.com/w3style.xsl">

<xsl:namespace-alias stylesheet-prefix="wxsl" result-prefix="xsl"/>

<xsl:template match="/">
  <wxsl:stylesheet>
    <xsl:apply-templates/>
  </wxsl:stylesheet>
</xsl:template>

</xsl:stylesheet>