You might also get a player that comes from a background where talking like a rapper is just how everyone does.
How do you deal with these kind of differences if it's a problem for you?
The first thing I do is try to understand why they are "showing out", as we say in the south. I ask them if they feel like it's appropriate to talk/type that way and who they think might be offended by it and why?
If they have the mental capacity to understand that someone could and why they might be offended, that's negotiating grounds to bring them in line slowly.
The next thing is to explain to them that "Open Channels" such as "Trade Chat" or even "Guild Chat" are not necessarily the best places to talk about your privates or what favorite "positions" you like and why. These type of conversations are really limited to close friends and its better to work toward being close friends and keep the touchier topics for a much much smaller audience ... say less than 5 people.
If you can't seem to get through to them. You might have to give them options. Options including submit, desist, or perhaps find another guild that is more like-minded. Never cave, or you'll lose ground.