Hmm...given how you've been writing about her, I'd suggest going into Crusader Kings 2\common\job_titles.text and removing the 'is_female' line from Marshal, if not any other jobs. That will allow her to be Marshal and troop leader in truth rather than just in writing.
This will also allow other women, like our bookish Duchess, to also lead troops and be marshal.
Now, admittedly, you'll also need to go into Crusader Kings 2\events\job_marshal.txt and remove the male-only restrictions on the various events if you want to make it 100% proper(Otherwise you won't get ANY of the marshal events, for good or ill).
I could understand if you preferred to just leave it. Or you could go the whole hog and unlock the other jobs too.
This will also allow other women, like our bookish Duchess, to also lead troops and be marshal.
Now, admittedly, you'll also need to go into Crusader Kings 2\events\job_marshal.txt and remove the male-only restrictions on the various events if you want to make it 100% proper(Otherwise you won't get ANY of the marshal events, for good or ill).
I could understand if you preferred to just leave it. Or you could go the whole hog and unlock the other jobs too.