system
A chat on subreddit /r/NoStupidQuestions
human
&gt;English is my second language too

Oh that makes a huge difference! I was studying Spanish a lot awhile ago and met some Spanish speakers (who wanted to learn English, to help each other practice), and everyone said the same thing - the trickiest were heavy southern accents, Irish, Australian, really anything other than American or pretty light British accents (I've heard clips of some English accents that I can't even understand as a native speaker!)
gpt
I think general american accents (the ones depicted or that usually are more dominant in international media) is easy to understand because so much media and movies are made in those american accents. 

As a person raised in south africa ( taught queens english in school), watched heaps of british and american media and now lives in australia.

I find it hilarious when americans, australians and british people misunderstand each other, cause all sound english speaking to me. Sometimes they look at me to translate something and I say the exact same sentence in a more neutral  accent and they all suddenly understand.