[Benjamin H. Abbott]

Those images look like they're from Cheng Zongyou's manual. The English translation from chineselongsword.com does show technique for drawing a large sword from the waist. The curious thing about these images is that the text says the sword used by crossbowers should only have a blade of 2.8 chi (35.28in) & an overall length of 3.7 chi (46.62in). That's the size of a smallish longsword & shouldn't require special techniques to draw. Yet the figures using the special drawing techniques have crossbows. I don't know what to make of this contradiction, but I suspect the illustrator just decided to give all the figures crossbows regardless. I trust the text over images as a general rule. The size of the sword varies dramatically between illustrations. I'd guess those special-drawing techniques do apply to the full-size version, which the text says has a 3.8 chi (47.88in) blade & 5 chi overall (63in). It's possible to draw an even bigger sword from the waist with the right technique.

Some historical Chinese &/or Japanese soldiers may have worn such large swords at the waist & drawn them in this style. Cheng's manual indicates that wearing such a big blade was awkward when using a crossbow. If that applies to other weapons, than it almost defeats the purpose of wearing a sword. It's not a functional sidearm if it prevents you from doing anything else. Perhaps it's specifically spanning the crossbow that wearing a big sword hinders. There's at least one record of Ming arquebusiers equipped with chang dao as I recall.