That wasnt a Longsword mate, that was a fullblown Claymore... which isnt made for 1v1 Combat since its just Bulky. Greatswords were used to create Space around the wielder and to break some Bones (Greatswords werent as sharp as they are portraied in Media).
Also, Crossguards dont do shit against Greatswords. Trying to block or parry would just break your wrists and disarm you on the spot.