немного соврал уважаемые, вот код, в общем
fun main() {
//input date format: 2021-02-15T01:00:00-08:00
//output date format: Mon Feb 15 2021
//output time format: 08:00
val inputDateTime = "2021-02-15T01:00:00-08:00"
val formatter = DateTimeFormatter.ISO_OFFSET_DATE_TIME
.withResolverStyle(
ResolverStyle.SMART)
val accessor = formatter.parse(inputDateTime)
val localDate = LocalDateTime.from(accessor)
val formattedDate = localDate.month.getDisplayName(TextStyle.SHORT, Locale.getDefault()).capitalize()
print(formattedDate)