My issue with that scene was that they showed she gave him a hard time and was able to keep up, her sword just broke. I don't think there were be many knights that can face the archduke the way she did. So even if she isn't the absolute best, she qualifies more than some of the other male knights.
That's the thing I hate about some of these "strong women" stories - just being strong isn't enough, she has to be unusually strong if not the strongest to be seen similarly to weaker less talented men.
Strength isn't the only factor. Practice, experience and skill, speed, paying attention to details/weak spots, confidence, and so many more factors are needed.
So a distracted guy that's holding back because he's underestimating her won't do as well, a bigger guy that's never held a sword won't know how to position himself to swing it, and another knight with more training might not be as fast/clever/whatever other related skill even if he is physically stronger.
That's why a smaller guy might be able to beat a bigger guy, since it's not always just about pure strength.
But yeah strength does help make up for other areas someone is lacking in sometimes since it is an important factor.
I fucking hated the beginning, it just seemed to make her look weak and inferior to a man, without the help of a magic force. I would've understood the difference in swordfighting skills if she only just now started training but she's been training and practicing for life, so it completely proves what in theory it wants to disprove.
Moreover they make her look idiotic, and make her the comic relief in the promo, only looking scary. Meh maybe will try it again after some time passes and my anger subsides