I like to think that at some point Ed got bored and decides to become a professor at some big name Amestrian college.
His specialty is a military funded class called Battle Alchemy, which he starts off by inviting any of his students to beat him in hand to hand for a conditionless passing grade (by the end of the first class, most students walk away sore and horrified).
It takes half the semester before they realize that Ed continues to beat them even when they use alchemy and he does not. They ask to see him use alchemy in battle. The next day, a man who looks almost the same as their professor shows up to class- he’s softspoken and polite, and the students expect a substitute lecture. Ed sits in the stands and laughs as Al proceeds to fight the entire class at once, and beat all of them. The students never ask again.
(And sometimes, in the middle of practicals, students swear they can see the Fuhrer watching from the edge of the field.)
I can also see him causing a hell of a problem when it comes to conventional textbooks-
“This is definitely wrong.”
“Sir, this is the most recently updated textbook for theoretical alchemy-”
“Yea fuck that, I can prove that soul alchemy isn’t unviable- someone hand me some chalk, I’m about to commit a mathematical felony.”