So, I’ve seen this problem when people want to write characters from a culture other than their own:
- They know that those characters speak a different dialect than they do
- And they want to convey this
- But they don’t realize the dialect actually has a…
Terry Pratchett is one of my favorite authors. I can think of half a dozen instances where one of his characters’ unusual speech or pronunciation is written out phonetically to give a sense of personality. Sometimes this is over-the-top off the wall, for humorous effect, as it has no real-world equivalent that I know of (Mr. Tulip’s speech impediment in ‘The Truth,’ Findthee Swing in 'Night Watch,’ Edward d'Eath in 'Men at Arms.’).
Another favorite author of mine, Tad Williams, wrote my favorite series Otherland without making accents and nationalities obvious in dialogue with a few exceptions (Long Joseph Sulaweyo, Daniel Yacoubian spring to mind), to the point where I would forget a character was British or Australian. That effect worked really well for me to confuse identities and cast mystery, which added to my enjoyment. Some characters had unusual speech patterns or slang that conveyed personality in memorable ways without being distracting or obfuscating.
In the hands of skilled writers, both approaches worked for me personally, but it wouldn’t surprise me if the very things that were fine for me offended or turned others off. Everyone has different triggers and thresholds. I’ve found there are certain words and ways of expression that are much more likely to cause offense, and others much less likely.
Unilateral arbitrary rules don’t tend to work well in communication, and certainly that seems to go double for creative expression. If you’re concerned about causing offense, I’d recommend getting feedback from people in a position to understand and have a valuable point of view (e.g. those you want to avoid offending), and err on the side of caution. Be creative in what solutions you try. Figure out what you want to convey and all the ways of doing it. I as a writer love trying different things and coming up with creative solutions.