Como dizer "gozar com o pau dos outros" em inglês

Could be someone that takes credit for somebody's else ideas.
Other case is of those someone that doesn't have ideas of their own/a mind of their own. People with no ideas of their own (usually "sheeps" or "followers" - follow others like sheep).
You could 'corner' the opponent by accusing him "you don't make/form an argument of your own".

Also, in the realm of opinions or ideas you could call someone "gullible" (they would fall for fake news easier, for instance), for lack of critical thinking.

There is also the worker or student that "doesn't pull their weight."

All goes with the context, of course. Let's wait for more, though.
It worth noticing that the sentence in Brazilian Portuguese may sound dirty, swear words, so the foreign people be careful with it. Mainly when talking to older people.