stix-fonts/stix-fonts-sizes-fontconfig.conf

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
  <alias binding="same">
    <family>STIXSizeOneSym</family>
    <accept>
      <family>STIXGeneral</family>
    </accept>
  </alias>
  <alias binding="same">
    <family>STIXSizeTwoSym</family>
    <accept>
      <family>STIXGeneral</family>
    </accept>
  </alias>
  <alias binding="same">
    <family>STIXSizeThreeSym</family>
    <accept>
      <family>STIXGeneral</family>
    </accept>
  </alias>
  <alias binding="same">
    <family>STIXSizeFourSym</family>
    <accept>
      <family>STIXGeneral</family>
    </accept>
  </alias>
  <alias binding="same">
    <family>STIXSizeFiveSym</family>
    <accept>
      <family>STIXGeneral</family>
    </accept>
  </alias>
</fontconfig>