Hcfyk

Normally I would use 일 하다 to express that I (or someone else) works somewhere - e.g. 나는 출판사에서 일한다. But I wonder if this is a bit 'childish', or if it focuses on the action of working rather than the state/status of having a particular job.

What are natural ways to make statements like "I work in a publishing company", "I work from home", "I work for Samsung" ?

To me, at talking a job, childish is natural.

I work in a publishing company

출판사에서 일합니다.

I am in a publishing company 출판사에 있어요

I go to a publishing company 출판사 다녀요

If we have a particular job, for instance lawyer. It has a character as like a free
lancer, then we can express the state easily. But, as like office man, if he is in an organization,
then we do not know well about a ranking or a position. Hence usually, we say one in the above three
and give a business card.

You already know the most natural way to say that.

"나는 출판사에서 일한다" sounds perfectly normal in a neutral context. "일하다" conveys both meanings of (1) the action of working ("오늘은 대충 일했다." I didn't work hard today.) and (2) having the status of a particular job.

"I work from home" would be "나는 집에서 일한다" and "I work for Samsung" "나는 삼성에서 일한다."

Some more examples from the Korea University Korean Language Dictionary:

(1) To mean the action of working,

그는 아내를 잃고 나서 두 아들을 잘 키워 내기 위해 부지런히 일했다.

He worked hard to raise his two sons after losing his wife.

(2) To mean the status of having a particular job position,

나는 중년이 되면 사회봉사 기관에서 일할 생각이다.

I'm thinking of working for a social service organization in my middle years.

For that, you can also use 근무하다 instead of 일하다. Although it may not be as natural as 일하다 would sound, it's always a good way to go for formal statements.

출판사에서 근무하였다. 근무하고 있다.

출판사에서 근무한 경력이 있다.

재택근무하다.

ㅇㅇ(회사)에서 ㅇㅇ(직책/직무)(으)로 근무하였다.