eaDocX can already use different Word paragraph styles for the Notes field of diagrams: it’s specified in the ‘Diagrams’ part of eaDocX Options and Settings.
I sympathize with your issue with DOORS: EA seems allow all kinds of strange formatting to be imported into Notes fields, and whilst eaDocX tries to make sense of what it finds, sometimes it’s just too strange….
We’re just completing work on v3.4 which, with the new ‘scripting’ feature, should give you much more control over the details of formatting, where you have requirements like this which fall outside of ‘regular’ eaDocX function.