As there is no eM Client app as far as i know, you normally can only view Notes via a browser on a computer or with a separate app.
eg: I currently use the Gmail app with my Gmail account in eM Client and can view (as you said) email, and calendar, and use “Google Keep app” separately to view my personal Google Notes.
I have seen mention in some EMC threads talk of a down the track possible eM Client app which then you maybe able to view Notes in the app if that is programmed down the track.
See this thread on a Mobile App - Mobile alternatives - Mail - eM Client