Feature Trees are visual a way to organize requirements in software. Apart from Use Case diagrams, UML offers no visual modeling of requirements.
It seems it would be possible to do feature trees in DOT. But from my (basic) understanding of DOT, it looks like an advanced feature (because of the way the tree is drawn).
It would be useful if there was a PlantUML mode such as @startfeaturetree/@endfeaturetree
Here's the example I posted on stackoverflow:
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