I talked too soon. This won't work, and I have no idea why:
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\setuplabeltext [en] [and-1={{, }}, and-2={{ and }}] % Should be: 1, 2 and 3
\setuplabeltext [es] [and-1={{, }}, and-2={{ y }}] % Should be: 1, 2 y 3
\setuplabeltext [de] [and-1={{, }}, and-2={{ und }}] % Should be: 1, 2 und 3
\starttext
\commalistsentence[one,two,three,four] % works as expected
\language[es]
\commalistsentence[uno,dos,tres,cuatro] % takes [en] settings
\language[de]
\commalistsentence[1,2,3,4] % takes [en] settings.
\stoptext
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If I change \mainlanguage, the main language is used in all three cases.
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Los fines no justifican los medios, porque la medida verdadera de nuestro carácter está dada por los medios que estamos dispuestos a utilizar, no por los fines que proclamamos.
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“You develop an instant global consciousness, a people orientation,
an intense dissatisfaction with the state of the world, and a compulsion
to do something about it. From out there on the moon, international
politics look so petty. You want to grab a politician by the scruff of
the neck and drag him a quarter of a million miles out and say, ‘Look at
that, you son of a bitch.’” — Apollo 14 astronaut Edgar Mitchell