The best way to find out the exact phrasing for your profession is to check what you have filled on your 'new business application form' to the Finanzamt, also known as the amazing Fragebogen zur steuerlichen Erfassung. On this form, under 7, you can see the profession you've stated.
Another way would be to check for the approval letter you've received from the Finanzamt. This letter, usually containing your new tax number, also includes the profession title as registered by the Finanzamt.
Confirmation letter from the Finanzamt (sensitive details removed)
Note although there were cases where the Finanzamt has accepted English-written professions, it's highly recommended to input your profession in German. A (partial) list of professions translated from English->German can be found here.
Also, profession length is limited to 25 characters, as stated by the Finanzamt.
Sorted tax guides are provided without liability and do not replace a tax advisor.
To get an accurate answer for your specific case, please consult a tax advisor.
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