yeah, that's what he got for tracing a knock off instead of doing the research. Most of the other blades I've seen him do were nice, even the Mek'leths he showed in the beginning, but that Bat'leth was shaped all wrong, it's not even smooth, if you look at it there's a big bump in the inner part between the two inboard prongs.
Actually the variation of the bat'leth he is using was a canon variation. Some of the various scenes these were used for the larger actors because the smaller curves design looked too small and not intimidating enough. It was also used for some of the more hardcore scenes because they could better predict the blade movements with the flatter mid-blade, the size was also for the same purpose.
If you actually got through all of the scenes throughout ST when Bat'leths were used you'll actually see several different variations, although the variations can be quite slight.
Might be a legit variation, but it lacks the flow of a bat'leth... Not that I'd want it swung at my head... Personally, I would rather have a mek'leth, way more versatile and practical... Try defending your home with a bat'leth, and you're going to wind up catching the walls, a mek'leth wouldn't have that issue