Looking through some NPC Klingon statblocks in the Klingon core book, I noticed that all of those with a bat’leth as an Escalation option had the Cumbersome quality on their weapon. Checking the weapons table in the Equipment chapter, the Heavy Blade option that the bat’leth falls under doesn’t have that quality.
Also, checking my copy of the Starleet core book, the Klingon NPCs there don’t have Cumbersome bat’leths. Which option do you think is correct?
I actually don’t mind the idea of bat’leths being Cumbersome, seeing as their use seems to be largely ceremonial and/or cultural. Though they are still weapons, and a weapon that takes a Prepare action to use may not be practical on the front line. Not that taking a sword to a disruptor fight is exactly an optimal decision, but that’s Klingons for you 
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