I don't want to convert numeric times to different locales, but this is what all my searches lead me to. I need to convert the actual words "Days", "Hours", etc. to the user's locale equivalent (e.g. "Jours", "Heures", etc.), and I need the abbreviations also.
Is this doable natively in JavaScript?
You can use Intl.DateTimeFormat():
The Intl.DateTimeFormat() constructor for objects that enable language-sensitive date and time formatting.
An example:
var date = new Date();
let o = new Intl.DateTimeFormat("fr-FR" , {
timeStyle: "full",
dateStyle: "full"
});
console.log(o.format(date));