My wolf character, Caralyn, has a strong Highland accent. It seems to be one of those accents that doesn't come across well in typing and is better heard audibly. But there were parts of the accent I could put across like using 'wee' instead of 'small' or 'little'. I also made a note in my character's bio what sort of accent or voice they have so it's easier for people to imagine.
When people say stuff like "You're being illiterate," they're just being silly. Have an open mind and think, not everyone speaks with an American or an English accent, just like in the real world. You have people who speak very different across the country and across the world. If people thought more of how dialogue sounds rather than how it is spelt, then it'll be a lot easier.