Just wants to mention that this thread, and joining a discord server with a lot of JP speakers, got me to try out using ChatGPT for “how do you say xyz”, when I’m stuck on a sentence. The way I do that is: 日本語で「thing I wanna say」, and then append things like タメ口 or 女らしい, depending what I want. I then use those as references to compose my own sentence. That said asking it in English will give you some more explanation
For an example of what it spits out: Luna's Learning Log - #602 by 暁のルナ
My impression is that it is useful for this, but again, I wouldn’t recommend until you have a certain base knowledge. I also tried out Gemini, and really disliked both its output and formatting for Japanese.