The classic short beatin' stick; it can be an escrima or police baton or sometime similar.
A length and maybe width morphable prop with it would be nice but not really a deal-breaker.
Using a short stick has an entirely different set of movements than using a baseball bat - there are some poses out there for the bat but almost none for the short stick save for a Gen2 Escrima pose set from The Before Times.
The beating part is more important that the being beaten part by far - there are pose sets of 'fend off attack' - but more are never bad,
The classic hover over victim, threatening; swing-and-a-miss, swing to the side, swing up and down, block an attack with the stick, two handed, like you were playing drums.
Level matter in this; many of your classic beatin' stick moments assume the victim is crawling or kneeling,. But there should be some for standing up, or attacker in pursuit.
One you seldom see is the 'poke the bear' pose, where you're prodding or probing with the stick.
Violent moves are certainly included in this but some subtler ones might be useful for the common variant: the electrified beatin' stick/the shock rod. Threatneing or caryin the stick poses are also good.
For victims, protecting the head is a classic pose, but any defensive move is good.