I was wondering wether the size of the weapon made an impact on the fight. Specifically I see duels with Claymore type weapons depicted as longer and more intensive.
While claymore specifically refers either to the Scottish two-handed sword or the Scottish basket-hilt sword, you're in luck. Fighting with the longsword is, dare I say, the best "preserved" historical martial art, due to fechtbücher, so called fencing manuals, by people like Hans Talhoffer. Video example. If you want to learn more about the actual fighting techniques, you should ask around on /r/wma.
