wp-calypso/client/my-sites/site-settings/date-time-format/default-formats.js

import { translate } from 'i18n-calypso';

export function getDefaultDateFormats() {
	return [
		...new Set( [
			translate( 'F j, Y' ),
			translate( 'Y-m-d' ),
			translate( 'm/d/Y' ),
			translate( 'd/m/Y' ),
		] ),
	];
}

export function getDefaultTimeFormats() {
	return [ ...new Set( [ translate( 'g:i a' ), translate( 'g:i A' ), translate( 'H:i' ) ] ) ];
}