Further to my previous answer and your comments.
https://fulbrightscholars.org/visiting-scholars/guide/taxes
There is nothing on this page that indicates that a Fullbright scholarship is wages. Wages are compensation for work performed, and even though you may have duties as a Fellow, anything you do that is part of education or training is not considered work performed.
Furthermore, since this is not earned income, it is not eligible for the foreign earned income exclusion, even if you performed your duties overseas. If you are a US citizen or green card holder, you are required to report this income and pay taxes on it. Fullbright indicates they pre-pay the taxes, but you must still file a tax return and report your income and whatever taxes were prepaid on your behalf, along with any other income you might have (investments, other scholarships, side jobs, etc.).
