From DataManager? No. DataManager is designed to work with data. Sending plain emails is more the job of an email client. You can use the scheduler to send an email on a schedule, but I don't think this is what you want.
Please edit or repost this in Ideas if you really want it - if we get sufficient demand, we'll consider it.

it is intented to send out an email in case an data update has been done. The email informs dashboard users that the dashboards have been refreshed.
Attaching a file is not necessary in this case.
In case the scheduler can do what I want, that's fine