For a while, growing up in
France when I was younger, people had no clue how to pronounce
Chelsea. Hard Ch, or soft Ch. What do you do with the end, -sea like the body of water, or see-ah? It was a mess. It was almost a named invented to tongue tie French people it seemed.
In the states most people say it right because I guess it was more common, but some people still say see-ah at the end.