LMASDLKJ JYN the answer is yes, yes she can, even though he's not going to be gung ho on the whole part of beating others up, he'll definitely want to learn how to get away/mitigate/prevent trouble, which by default tends to mean learning how to beat people up. But refraining from doing so. He's not a violent man by nature or inclination, for sure!

He's 100% happy to bemuse her with the amazement of his professional athletic career. He's Got This On Lock. (Plus, at least it'll make sense why he's got great reflexes and is in great shape, just... not trained for anything self-defense oriented!)