This is the one I use. It’s rechargeable with a USB cord. I have never been questioned about it and I’ve been on 14 cruises since I bought it in Nov 2022. Before that I used a fan that had to be plugged in for years and I was never questioned about that either.
https://www.amazon.com/gp/product/B0992KV5SK/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1