Low flutes (alto, bass, contra)
Are there sound fonts for the low flutes? Piccolo and C flute are standard, but there's a lot of literature for alto, bass, and contrabass flutes. For alto one can write below the C flute range but the notes show as red.
Comments
There are more flutes available, sure alto, bass and contrabass, just not in the commone instruments list. And unrelated to whether there's a separate sound in a GM soundfont for them (which I doubt)
But presumably, if you do a web search, you will indeed find soundfonts for those instruments, and you can then use them in MsueScore as described in the Handbook under that topic.