[Doitsu]

Originally Posted by Notjohn

Kevin, does that work with any embedded font/language?

If you're referring to the CSSFromFont plugin (which I wrote), all it does is add font import statements to the main CSS file or a new CSS file, if no main CSS file exists.

For example, if you add the 4 Charis SIL fonts to the Fonts folder and run the plugin, it'll add the following:

Spoiler:

@font-face {
    font-family: 'Charis SIL';
    font-weight: bold;
    font-style: normal;
    src: url('../Fonts/CharisSIL-B.ttf');
}

@font-face {
    font-family: 'Charis SIL';
    font-weight: bold;
    font-style: italic;
    src: url('../Fonts/CharisSIL-BI.ttf');
}

@font-face {
    font-family: 'Charis SIL';
    font-weight: normal;
    font-style: italic;
    src: url('../Fonts/CharisSIL-I.ttf');
}

@font-face {
    font-family: 'Charis SIL';
    font-weight: normal;
    font-style: normal;
    src: url('../Fonts/CharisSIL-R.ttf');
}

I.e., you'd still have to add font-family: 'Charis SIL'; to one of your styles for the embedded font to work. It's definitely not a turnkey solution!
Ebook designers with limited technical skills might be better off using Calibre for font embedding. (Preferences > Conversion > Common Options > Look & Feel > Embed font family.) For more information see the Calibre documentation.

Originally Posted by Notjohn

Now that the KDP claims to support five Indian languages, there are many appeals on the KDP forum for help when the system doesn't seem to work for individual authors.

Actually, Amazon added Indic Google Noto fonts, e.g. Google Noto Sans Bengali, to the firmware of all current eInk models back in January 2017.
I.e., KDP authors from India won't have to embed any fonts at all. Other authors also will rarely need to embed fonts for Kindle books, because current Kindle models and apps come with Code2000, which covers most Unicode 5.2 glyphs. (They also come with CJK fonts.)

If you have more Kindle font questions, please post them in the Kindle Formats forum.