The technique applied is not randomly selecting a different typeface per paragraph, but tweaking the glyph shapes when a character is repeated. Glancing at the LibreOffice extension, it seems to slightly vary CharScaleWidth by 90–110% and CharEscapementHeight by 97–100% of the base height.

cool, thank you!

METAFONT in particular does not have a way to write code to produce different random variations for the same glyph, nor does its output format have a way to encode those multiple alternatives in its output. I'm not sure if PostScript Type 1 fonts do either, but I'm less familiar with them.

Clever to apply on a restaurant menu (like in example on page 7). It makes the dishes feel more outstanding, special therefore justifying the price. Which other examples could make sense?

I made a brief attempt of splitting each character into a separate <span style="transform: scale(<random>, <random>)">c</span>, but it doesn't look good because the transform is applied after the glyph is rasterized. I didn't see a way to scale the font size itself in two different axes, and applying a single scaling factor of 97-100% does not perfectly recreate the effect. text-rendering: geometricPrecision probably helps.