TwoTone varied Material Symbols Icons of Material 3 Expressive, article at https://open.substack.com/pub/fredgrott/p/getting-material-symbols-in-material?r=26egx&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true

snippet.dart

 MaterialSymbolsBase.setOutlinedVariationDefaults(
        color: Colors.red,
        fill: 1,
        weight: 300,
        grade: 0,
        opticalSize: 40.0);
    MaterialSymbolsBase.setRoundedVariationDefaults(
        color: Colors.blue,
        fill: 0,
        weight: 400,
        grade: 200,
        opticalSize: 48.0);
    MaterialSymbolsBase.setSharpVariationDefaults(
        color: Colors.teal,
        fill: 0,
        weight: 600,
        grade: 0.25,
        opticalSize: 20.0);

    // then use VariedIcon.varied() to create your icons - instead of Icon() directly
    Icon example = TwoToneIcon.varied(twoToneVariation:TwoToneVariation.filled_first, Symbols.developer );