When a trader is trading options in "chop" are they mostly going long or short or both?
You don't necessarily "short" options...atleast in the same sense of '
borrowing' stock to short;
You simply bet down, or buy the Put option.
But to answer your question, it's hard to say what a trader has specifically in mind or is doing,

You only generally do both/straddle when you expect an explosive volatility move.
So again, to answer your question, ...that trader is most likely directional upwards and/or downwards on what they perceive to happen next,
Trading is very, very basic -- it's far from rocket science,
I even think 'dumber' common sense, observant people are generally more successful with trading...rather then people with professional degrees and engineering and medical stuff.
Give me a guy who hangs around NYC Times Square all day...I bet he'll be a better trader than a random suit with a master's degree,
(i feel like the Duke Brothers from Trading Places)