I’m in the US so I’ve mostly watched US TV shows, I’ve been wanting to watch shows made by other countries as there must be some great ones that never took off in the states.
I’ve seen a few I could recommend like Alice in Borderlands (Japanese), Gangs in London (UK), Lupin (French)
Not foreign for OP.
The question was what my favourite foreign TV series is, not what my favourite one of their foreign TV series is
Based on their post, the intent was foreign for them. Not foreign for you. That’s why they said they were in the US and wondered what shows didn’t take off in the US.