The expression はそっちのけで / をそっちのけで means "ignoring," "neglecting," or "setting aside" something that should normally be attended to, and instead doing something else. It carries a nuance of criticism or surprise – the speaker implies that the thing being ignored should be prioritized, but the subject is paying no attention to it.
そっちのけ literally comes from そっち (that direction / that side) + のけ (derived from しりぞける退ける, meaning "to push aside"), so it conveys the idea of "pushing something off to the side."Both は and を can be used before そっちのけで. The particle は emphasizes contrast – highlighting what is being neglected in contrast to what is actually being done. The particle を simply marks the neglected object more neutrally. In practice, both are common and largely interchangeable.