This is coming in the new version of Outlook.com. If you don’t already see it, you should soon see “Reply all by meeting” in the drop-down menu next to “Reply” when you click on a specific email. Hope that fits your needs. Thanks for the feedback.
An error occurred while saving the commentdani commented
I see on the outlook app you can reply all then click on the calendar icon to add that email to the calendar as an event it send to all in the original email - it does not let you delete any of the emails on the chain or put in an exact time - you can choose a time on the hour or half hour but not any other times like :20 or :35 past the hour