Ubuntu 的 Fontconfig 默认优先匹配日文（JP）字形。

cat /etc/fonts/conf.d/64-language-selector-cjk-prefer.conf

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
    <alias>
        <family>sans-serif</family>
        <prefer>
            <family>Noto Sans CJK JP</family>
            <family>Noto Sans CJK KR</family>
            <family>Noto Sans CJK SC</family>
            <family>Noto Sans CJK TC</family>
            <family>Noto Sans CJK HK</family>
        </prefer>
    </alias>
    <alias>
        <family>serif</family>
        <prefer>
            <family>Noto Serif CJK JP</family>
            <family>Noto Serif CJK KR</family>
            <family>Noto Serif CJK SC</family>
            <family>Noto Serif CJK TC</family>
        </prefer>
    </alias>
    <alias>
        <family>monospace</family>
        <prefer>
            <family>Noto Sans Mono CJK JP</family>
            <family>Noto Sans Mono CJK KR</family>
            <family>Noto Sans Mono CJK SC</family>
            <family>Noto Sans Mono CJK TC</family>
            <family>Noto Sans Mono CJK HK</family>
        </prefer>
    </alias>
</fontconfig>

通过用户级配置强制优先加载简体（SC）字形。

mkdir -p ~/.config/fontconfig/conf.d

cat > ~/.config/fontconfig/conf.d/80-prefer-sc-override.conf << 'EOF'
<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
  <alias>
    <family>sans-serif</family>
    <prefer>
      <family>Noto Sans CJK SC</family>
      <family>Noto Sans CJK JP</family>
      <family>Noto Sans CJK KR</family>
      <family>Noto Sans CJK TC</family>
    </prefer>
  </alias>
  <alias>
    <family>serif</family>
    <prefer>
      <family>Noto Serif CJK SC</family>
      <family>Noto Serif CJK JP</family>
      <family>Noto Serif CJK KR</family>
      <family>Noto Serif CJK TC</family>
    </prefer>
  </alias>
  <alias>
    <family>monospace</family>
    <prefer>
      <family>Noto Sans Mono CJK SC</family>
      <family>Noto Sans Mono CJK JP</family>
      <family>Noto Sans Mono CJK KR</family>
      <family>Noto Sans Mono CJK TC</family>
    </prefer>
  </alias>
</fontconfig>
EOF

刷新字体缓存

fc-cache -f

验证

# 应返回 Noto Sans CJK SC
fc-match 'sans-serif:charset=590d'