How to make variable text as Xpath expression - xslt-2.0

Question

Please suggest to get Xpath expression from the variable text. As xpath expression is stored in a variable as a text. From earlier suggestions were suggesting evaluate function, but unable to get.
XML:
<article>
<float>
<fig id="fig1">Figure 1</fig>
<fig id="fig2" type="color">Figure 2</fig>
<fig id="fig3" type="color">Figure 3</fig>
<fig id="fig4" type="color">Figure 4</fig>
</float>
XSLT 2.0:
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
<xsl:template match="#*|node()">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:param name="varColorFig"><xsl:text>//float/fig[#type='color']</xsl:text></xsl:param><!-- Xpath stored in variable as a text-->
<!--xsl:variable name="names" as="element(name)*"><xsl:evaluate xpath="$varColorFig" context-item="."/></xsl:variable-->
<xsl:template match="article">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
<xsl:element name="ColorFigCount">
<xsl:if test="count(//float/fig[#type='color']) gt 0">
<a><xsl:value-of select="count(//float/fig[#type='color'])"/></a>
</xsl:if><!--real Xpath expression format-->
<xsl:if test="count($varColorFig) gt 0">
<b><xsl:value-of select="count($varColorFig)"/></b>
</xsl:if><!-- xpath stored in variable as text, then needs to get as Xpath here, but it is not processing as Xpath.-->
</xsl:element>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Required Result: <b>3</b> is the required, but now getting 1.
<article>
<float>
<fig id="fig1">Figure 1</fig>
<fig id="fig2" type="color">Figure 2</fig>
<fig id="fig3" type="color">Figure 3</fig>
<fig id="fig4" type="color">Figure 4</fig>
</float>
<ColorFigCount><a>3</a><b>3</b></ColorFigCount>
</article>

Answer 1

In XSLT 3 with xsl:evaluate support your code would look as follows (assumes expand-text="yes" is enabled):
<xsl:param name="varColorFig"><xsl:text>//float/fig[#type='color']</xsl:text></xsl:param><!-- Xpath stored in variable as a text-->
<xsl:variable name="names" as="element(fig)*"><xsl:evaluate xpath="$varColorFig" context-item="."/></xsl:variable>
<xsl:template match="article">
<xsl:copy>
<xsl:apply-templates select="#*|node()"/>
<colorFigCount>{count($names)}</colorFigCount>
</xsl:copy>
</xsl:template>
The xsl:param could be shortened to <xsl:param name="varColorFig">//float/fig[#type='color']</xsl:param>, I don't see a need for xsl:text.