How to control text signature for email drafts using MailKit(Mail Extensions) on MacOS?

I am currently working on a project where I need to control the text signature for email drafts using MailKit(Mail Extension) on MacOS. However, I am not sure if this is possible or not. I have not been able to find any information on this in the MailKit documentation (https://developer.apple.com/documentation/mailkit).

Signature selection

I want to control/switch by a dropdown the signature of an email draft using swift code extension with MailKit.

Has anyone had experience with this before? Is there a way to control the signature for email drafts using MailKit on MacOS? If so, could you please provide some guidance or code snippets on how to achieve this?

Any help would be greatly appreciated. Thank you in advance!