They look like awesome weapons in the first photo(on the mini), I can't see the grooves on them as any sort of issue, you would have to be fairly amazing with them to trap and hold peoples' weapons during combat, I also have a couple of axes which have hooked heads and similar grooves and have used them for years with no issue.
I also disagree that they don't (or at least couldn't) meet Alliance weapon guidelines, they could be made, exactly as per the first post as huge, chunky, totally safe LARP weapons.
I think ClavicusEVile has hit the problem with them right on the head though - they are 'punching type' weapons - a real danger in LARP combat, if they were even a little high or low in your hands you could strike with your knuckles or in the heat of combat swing and when they pivot in your hand hit someone in an uncontrolled strike.
I have seen true LARP tonfa and nightsticks being used in other LARP systems, but they are generally very experienced players, and, more often than not punching style weapons are just not permitted.
Seriously though those blades done as huge as they look on the miniature, with the sculpting and that painted finish would look amazing!