Is it possible to schedule email sends to go out in that person's time zone? For instance, if we schedule an email send at 9 am PT, is there a way we can also have it go out at 9 am ET, 9 am CT etc?
Yes, this is a feature on email programs. See Scheduling with Recipient Time Zone - Marketo Docs - Product Documentation
It is important to note that you can only use this function in the email program. Unfortunately, you aren't able to use it in default programs yet. (I hope someone corrects me here).
Check out this post and the comments - Deliver in Person Time Zone