It might be broken if it weren't for the fact that you can use it once for a short rest, after which it requires both hitting the enemy and the fact that the enemy will fail the condition check with which most of the stronger enemies will have no problems.
Why is it supposed to be a problem to remember a few effects? Unless we assume that players are idiots who cannot remember 5 effects (ignore the fact that you can always check what it does).
How is this different from the need to remember what color spray or maybe entangle does?
This is a mechanic that fixes what 5e broke, which means that the weapons are really different from each other and not just have different damage.
Every enemy has the ability to shove a character as a bonus action on every turn of combat. This shove has been increased in range to allow for easily knocking a character off a ledge that they should be safe from, dealing a ton of fall damage and potentially taking their next turn away to. Add to that the once/combat extra weapon abilities and the monsters that can leap half way across the map and do an AOE prone to your entire party and you can see where we may be coming from.
