Italics (or not) for non-English words
A while back on a Monday critique, I told Richard that I'd noticed he'd italicized the Spanish words in his work and that current thought on that is changing.
The guidance in Chicago Manual of Style* is that on first use, non-English words are italicized and then if the readers come across them enough that they'll learn them, the words are not italicized after first use.
That guidance applies to made-up words in a spec fiction book and to books set in our world with non-English words / words from other languages that are not in the dictionary. (If a word is in the dictionary--like déjà vu is--then it is not italicized).
Many authors and editors are now choosing to not put words from other languages in italics because the italics "others." But as a signal to readers that this might be an unfamiliar word, the italics might be used.
If you're self-publishing, of course it's your choice to italicize or not. If you are traditionally published, it may be something you need to talk through with your agent (if you have one) or the publisher.
This link will take you to a blog from 2020 at Chicago Manual of Style discussing when to use/not use italics: https://cmosshoptalk.com/2020/03/17/italics-for-non-english-words-in-fiction/
*Note that CMOS announced the next version is coming out this fall, so it will be interesting to see if this guidance changes.