Firstly, XSLT 1.1 doesn't exist. It was withdrawn quite a while ago. (Yes, there's boilerplate text on this forum that refers to it! It's obsolete too...)
This one's quite easy (in XSLT 1.0)
Code:
<xsl:template match="group/element">
<xsl:copy>
<xsl:copy-of select="@type|@name|../@shared"/>
</xsl:copy>
</xsl:template>
<xsl:template match="element">
<xsl:copy-of select="."/>
</xsl:template>