outlook.js onSend support for Office 2016/2019 (not connected to 365)

Question

The documentation for onSend support in office add-ins states:

The on send feature is currently supported for Outlook on the web in Office 365 (in preview), Exchange 2016 on-premises (Cumulative Update 6 or later), and Exchange 2019 on-premises (Cumulative Update 1 or later). This feature is also available in preview on Windows and Mac connected to an Office 365 subscription. Add-ins that use the on send feature aren't allowed in AppSource.

I'm wondering if the onSend feature will support the following configuration: Office 2016/2019 (not connected to 365) with Exchange 2016 on-premises. Office 2016/2019 (not connected to 365) with Exchange via 365

Answer 1

Please find the image explaining availability of onSend on different platforms