Apologies for discussing terms related to such an unpleasant topic.
The obvious Japanese translation of "comfort women" is "慰安婦", as the English term is a calque of the Japanese term.
However, how are they referred to nowadays, such as by the media? Do they use the term "慰安婦" as-is, or do something different, such as using something like so-called, adding the equivalent of scare quotes (apparently not done in Japanese), or choosing some term that is less euphemistic and more explicit?
Searching jisho.org for "comfort woman" or "comfort women" mainly got hits relating to 慰安婦, as did searching for "sex slave" or "sexual slave".
I tried looking at a google translated page of the Japanese-language Wikipedia article on 慰安婦. It was a little hard to read. The section 日本における呼称 seemed to be about how they were described at the time. The section 辞書、事典の記載 may or may not be relevant - I'm not sure if it's talking about what term was used, or whether it talks about how dictionaries or encyclopedias described what those terms meant. The section 従軍慰安婦」という呼称 has a couple of paragraphs that appear to be about terminology in the time between the war and now, and a single line paragraph saying that "いわゆる従軍慰安婦" is currently used by the Japanese government and NHK, which according to Google Translate means "so-called comfort women". That's the kind of information I'm after, but I'm not sure how reliable or complete that one-line paragraph is.
I also looked at the Japanese Wikipedia article 性的奴隷, but it mainly mentioned what terms specific organisations used, plus what the Yomiuri Shimbun used in English.