When I was a kid we went to Germany a few times to visit my grandparents. Most younger people could speak English and between my German and their English we were good. I didn't learn, fixin to, bless your heart, and all y'all, until I moved to Texas. Sweat tea too.
We didn’t know what to say first few times after sitting down in a restaurant (mostly Logan’s Roadhouse) and got asked:”y’all set?” We just went ahead and ordered but we didn’t really know what it meant what we were asked
Being a northerner living in the south, dealing with international people all over the globe daily I have to say southern speak (like talking to a true person from up in the moubtsins) is harder for me to understand than Japanese. On the flip side you have to adapt to your environment and even some of the basic southern words I picked up northerners have no idea whst I’m saying.